Since UPGRADE My cordless phone (landline) will not display correct time on it

2 weeks ago Comcast did a neighborhood UPGRADE. And since then the time on our handset will not stay correct. We fix it on the handset and then after first call comes in and it changes it to something NOT correct.

I escalated to a supervisor and they said it HAD to be the phone not Comcast. But they said to get a new phone. So I got a new phone.

I Plugged in NEW phone and before I could SET the time on the new handset, the phone populated with the WRONG time. This proves that Comcast signal sends the time info to the phone. This is on the Comcast side (xfinity) NOT the cordless phone side. They ignore me at their peril as I will shame them forever if they do not fix it. Its a provisioning issue (on the Xfinity side) NOT the phone manufacturer.  Anyone else having this issue - let me know.