- Spam
- Scam
02 5502 9721 (0255029721): 2 reports of silent voicemail calls from Gloucester, NSW. Repeated calls with no message left.
Silent Call Reports for 02 5502 9721
Two contributors have reported calls from 02 5502 9721 (also written as 0255029721), a local number registered to Gloucester, NSW. Both reports describe the same pattern: unanswered calls followed by silent voicemails with no audible message or caller identification. The number is associated with Symbio Networks Pty Ltd, a local service provider in NSW.
One contributor received an initial call on 22 December 2025 that went unanswered, followed by a second call on 6 January 2026 that left a voicemail of complete silence. A separate report describes an identical sequence, with a midday call on 22 December followed by another silent voicemail on 6 January. Both contributors found the pattern unusual enough to block 02 5502 9721.
What These Calls Indicate
Silent calls of this type often serve as line-testing for callback scams or verification that a number is active and monitored. The timing pattern across these two reports is notable: the same dates (22 December and 6 January) suggest either automated dialling or deliberate targeting. The fact that both calls were left unanswered yet voicemails were deposited, with no message content, is a common hallmark of robocall systems testing for active numbers.
While only two reports exist for 0255029721 so far, the identical timing and behaviour pattern indicates this may be part of a broader campaign rather than random nuisance calling.
Call Timing and Patterns
Both contributors received calls from 02 5502 9721 on 22 December 2025, with a follow-up silent call on 6 January 2026. One report notes the second call occurred at midday. The six-day gap between calls suggests a deliberate callback attempt rather than accidental dialling. Contributors who blocked the number have reported no further contact, indicating the caller may move on after two unsuccessful attempts.
What to Do If You Receive a Call from 02 5502 9721
If 02 5502 9721 calls you:
- Do not: Return the call or respond to any voicemail message, as this confirms your number is active
- Do: Let it go to voicemail, block the number immediately, and do not engage with any follow-up attempts
- Do: Be aware that callback scams often follow silent call testing - if you receive requests for personal information after blocking, report them separately
What to Do If You Receive an SMS from 02 5502 9721
If 0255029721 sends you a text message:
- Do not: Click any links or reply to the message
- Do: Forward the SMS to 0429 999 888 (Australian Communications and Media Authority spam reporting) and block the number
- Do: Save a screenshot of the message before deleting it, in case you need to report it
How to Report 02 5502 9721
If you receive suspicious calls from 02 5502 9721, report them through these Australian government channels:
- ACMA (Australian Communications and Media Authority): Report via acma.gov.au or call 1300 850 152
- Scamwatch: File a detailed report at scamwatch.gov.au if you believe this is part of a scam
- Do Not Call Register: Register your number at donotcall.gov.au to reduce unwanted telemarketing (though this number may not be telemarketing-related)
- Reverseau: Contribute your experience to help other Australians identify this number
Help others by sharing your experience with (02) 5502 9721!
WRITE A REVIEWRatings Distribution
What Our Users Reviewed
Repeated calls from this number, the first on 22/12/25 that was unanswered as I do not know anyone living in Gloucester, NSW.
Second call on 6/1/26 and left Voicemail of total silence. Blocked.
Called midday December 22, didn't answer. called again January 6 and left silent voicemail
Help others by sharing your experience with (02) 5502 9721!
WRITE A REVIEWFrequently Asked Questions
Why is 02 5502 9721 leaving silent voicemails?
Silent voicemails from 0255029721 are typically used to test whether a phone number is active and monitored by a real person. This is a common tactic in callback scams and robocall campaigns. By leaving a silent message and waiting for a callback or any response, callers can verify your number is worth targeting. Both reports of 02 5502 9721 show this exact pattern - unanswered calls followed by silent voicemails with no actual message content.
Should I call back 02 5502 9721?
No. Do not return a call to 0255029721 under any circumstances. Calling back confirms to the scammer or robocall operator that your number is active and that you respond to attempts to contact you. This makes your number more valuable for targeted attacks. Both contributors who received calls from 02 5502 9721 blocked the number instead, which is the correct response.
Is 02 5502 9721 a scam number?
02 5502 9721 (0255029721) is a Gloucester, NSW local number registered to Symbio Networks Pty Ltd. The silent call pattern reported by contributors is consistent with scam testing behaviour, though the actual scam attempt may not have progressed. Two independent reports describe the same suspicious sequence of calls, suggesting this number is being used for automated or semi-automated calling campaigns.
Why did 02 5502 9721 call twice with a gap between calls?
The six-day gap between the first call on 22 December 2025 and the second on 6 January 2026 from 0255029721 suggests a deliberate follow-up attempt rather than accidental dialling. Scammers often use this pattern: an initial test call followed by a retry if the first attempt goes unanswered. Both contributors received calls from 02 5502 9721 on these exact same dates, indicating a coordinated campaign rather than random nuisance calls.
What should I do if 02 5502 9721 keeps calling after I block it?
If 0255029721 continues to call after you've blocked the number, report each attempt to ACMA via acma.gov.au. Persistent calling despite blocking may indicate harassment or a more serious scam attempt. Both reports of 02 5502 9721 stopped after blocking, but if you experience ongoing contact, keep records of dates and times and escalate your complaint to ACMA with this evidence.
How can I verify if 02 5502 9721 is a legitimate number?
The number 02 5502 9721 (0255029721) is legitimately allocated as a local service in Gloucester, NSW through Symbio Networks Pty Ltd. However, legitimate service providers' numbers can be spoofed by scammers. The silent call pattern reported by contributors is not typical of legitimate business calls. If you need to verify whether a real Symbio Networks contact tried to reach you, contact them directly using a number from their official website rather than returning calls to 02 5502 9721.