New member phone line Issue Unable to get through

[#1]

Hello everyone,
Please can you offer help and advice?
People that phone us are unable to get through, please see full explanation below.
We recently switched from Sky and also was given a new phone number.  We have not changed any equipment apart from plusnet's router and filters.
Majority of people that phone cannot get through at all, this happens every-time.These are landline and mobiles that cannot get through. They have never been able to get through since change over to plusnet. It is not Intermittent. They get the message "the number you have dialled has not been recognised, please check & try again" and some people just hear silence. The people that are unable to get through are on different providers, BT, TalkTalk, Virgin etc.  Only a small minority of people are able to get through on this line. Those that can get through can get through all the time.
We can use the phone to ring out.
Has anyone else experienced this issue and what if any was the resolution? 
plusnet are aware of this and are trying to resolve the problem.
All responses would be appreciated.
Regards
Mr & Mrs W

[#2]

If you use your phone to call a mobile number, is the number displayed on the mobile the same as you had been assigned ?
*edit - and do you have any privacy options selected for the phone - i.e. refuse to allow calls which are from withheld numbers ?

[#3]

Quote from: picbits

If you use your phone to call a mobile number, is the number displayed on the mobile the same as you had been assigned ? *edit - and do you have any privacy options selected for the phone - i.e. refuse to allow calls which are from withheld numbers ?

Hi,
Thank you for replying.
Yes, phoned a mobile using the landline, the number assigned does display.
No privacy options on the phone. 
We had refuse withheld numbers and last call bar  with previous provider (Sky).  Those privacy options were on our old number with Sky.  We requested a new number when switching to plusnet.
The openreach engineers that have been to test the line have said that they have experienced this problem in the south of England.  We are in North West England.