Telstra customers have been inundated with missed call and voicemail notifications despite their phones never ringing.

But the telco quickly ruled out any sinister cause, attributing the incident to a MessageBank service issue.

Users took to social media to report receiving text messages about missed calls or new voicemails, some saying they were flooded by up to 100.

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“Anyone on Telstra getting some missed call texts from people tonight? No idea when these people have called me, possibly last week!” one person wrote on Facebook.

Others speculated the telco may have been experiencing a cyber-attack, writing: “Telstra currently going through a cyber-attack by the looks. Just got 100 missed call notifications.”

“Something weird happening with Telstra mobile’s at the moment, I got a text message saying I’ve had a missed call from someone but it didn’t appear as a missed call in my call log,I rang them but the confirmed they never called but they he’d the some thing happen a few times,” another person wrote.

A user shared a screenshot of a notification about a new voicemail from a call they did not receive. Credit: X

But Telstra was quick to dispel rumours of suspicious circumstances, instead telling customers it was an issue with MessageBank which has since been rectified.

“We experienced an issue with our MessageBank service earlier today, which has now been fixed,” a Telstra spokesperson said in a statement.

“You might notice a number of delayed missed call and voicemail notifications arriving all at once.

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“We’re sorry for how confusing this must be.

“There is no impact to triple-0 calls, voice calls or mobile data.”

Telstra came under fire in July after a national outage left millions of customers without mobile services.

A damning report released in September revealed two engineers primarily involved in the ultimately bungled software upgrade were on “mandatory standdown” at the time.