BT4600 Calling out problem

[lyntats]

My mother has a dual BT 4600, she has been calling me on my landline from it for over 18 months, but recently she has clearly done something her end to my landline number. When she tries to call me, she gets a pause, then gets an audible click and the call does not connect. She hasn't blocked me because I am able to call her landline from my landline and mobile.

I can't work out what she has done and I have gone through the online manual and no joy. Can anyone help me please before I have to reset it.

Many thanks

[rbz5416]

Is she calling from the contacts list or dialling the number manually? If the former does the latter work?

[lyntats]

She has tried both, she said it is not a click it is a sort of continuous err err err sound, if that makes sense.

[imjolly]

If either of you are with BT have you been moved to digital voice?

[lyntats]

Mum is with BT and has not had the change over yet, I am with Virgin Media, have made the change and the phone is connected through the modem, this was done months ago and all was ok. This fault happened about a week ago. It only appears that it is my number she is having the problem with, she can ring everyone else, including my mother-in-law who is also on VM modem connection.  She has deleted the saved contact and re-entered it too.