Question is three weeks old with no response? Bad forum, Bad (smack on butt with rolled up newspaper).
Suzq13: you still looking for an answer?
There is more than one way to look at your call history.
it appears that accessing with the xfinity connect voice option is limited to 90 days
No doubt comcast did that to limit the total space used on their servers to store calls
if you look at the billing area and follow these instructions:
Additional call records and itemized voice charges can be accessed in My Account:
then it does not have a 90 day limit. In mine I see calls back to 05/17, but it is outgoing calls only.
If you have a independent caller id device (like your phone) they are usually limited by total number of calls not age of call. but if you get more than x number of calls in three months then that is no help (my phone is limited to 50 stored calls).