We are currently experiencing some issues to numbers beginning with 0207112; where one way audio is being experienced on all calls. We are invetigating this issue with the originating carrier for the numbers and will post an update as soon as we know more.
Update. As of 12.25, this issue is resolved. The issue has been identified as a carrier - misconfiguration, we have implemented a work around on our side to bypass the carrier configuration problem.
We continue to progress the issue with our carrier to determine why the issue has arisen and in order to correct their configuration issue.