'mailbox is full' message on landline

[cdsatkins]

Hello,  my in-laws are unable to receive messages on their landline phone.    The BT Essentials phone does not have any messages on it and there is no option to delete that works on the handset.    I then installed a brand new Gigaset cordless phone &  with no messages yet on it, callers are still unable to leave messages as they hear 'Sorry, this mailbox is full' message

Anything to do with BT codes eg. 141 / 1471 / 1571 etc...?

Any ideas, we will be very grateful!   

[-Richie-]

It sounds like 1571 which is included free on Digital Voice, try the userguide which is found Here 

[cdsatkins]

Thanks Richie, I will give it a go & let you know. Chris

[cdsatkins · Accepted solution]

Thanks for the tip off Richie, it is 1571 -
I have now cleared all their messages. The challenge now is how to cancel 1571 service altogether!! Somehow it started collecting messages 22 Dec last year, however the in-laws are not with BT but with another provider!

[-Richie-]

Speak with their provider and have it removed, 1571 isn't exclusive to BT, other CPs use the same setup.