cannot remove Alternative mailbox to General Delivery

[Sam173]

I need to remove associated extension to General delivery and the system does not seem to allow it. It looks like once you've enter an extension and come back to remove it, the system does not allow a clear of leave it blank

 

[Dasheen]

return it to default by entering 1000 if u have no ext 1000

 

[Sam173]

just found out that pressing # on the Startalk removes it, hope that can also work on the BCM, will head out after lunch and try 1000, thanks