Keep getting a weird number 1001005080 ?? (ATT, email, sound, calling)

[councillor]

On my ATT cell, anyone know who this is that keeps calling ?

Thanks!!

[harry chickpea]

From a quick web search:

its your at & t voicemail calling you back that you have a voicemail,(or someone just hung up without leaving a message after the beep went off after your outgoing message). you have to call your voicemail and go into options (I think its the #4 key) to turn it off. My voicemail suddenly stopped alerting me with an alert sound so I turned on the callback to be notified and when it calls back it leaves that number 100 100 5080.

[councillor]

Thanks