Landline wont receive incoming calls

[rada]

My mother-in-law has had sky TV, broadband and talk installed at her porperty. Broadband is fibre to the porporty so Talk is via VOIP to the FTTP box in the house. She can make outgoing calls but cannot recieve any calls - if you dial her number it rings on the phone calling her but nothing at her end. We have checked that Sky has ported over the correct number as it shows her number when she rings us. Here is the confusing part I can call her using my Sky Mobile and it rings as normal but will not work from O2, EE or Vodaphone of any other land line ! 

I have been trying to get Sky to fix for a month now and they just keep doing the same thing of escalting to the Network and porting team who find no fault and then do nothing about it, despite it still not working.

Any ideas what the issue is?

[Highlinder]

@rada  Sounds like a routing issue and Sky should be able to deal iwith it. If you don't have incoming calls then there is a fault and Sky should get Openreach to deal with it.

[Kempster60]

I feel your pain Rada, 
 we have a very similar problem. 12 days into changing Broadband and landline from BT to Sky and still having problems. Anyone  using BT landlines or Sky mobiked can ring us but if I ring our new sky landline from my EE mobile it goes straight to BT answer phone!  I've spent 12 days chasing Sky and BT getting nowhere, Sky customer service has been appalling, even lied to me on day 10!  We felt only option was to make a complaint, which is bring I have to say is being  handled with intelligence and empathy, finally might be getting somewhere or we will have to cancel.