Claymore miner hasn't been updated in a long time. The cerificate was probably revoked because it expired.
This is a clue to look for another miner that is more actively maintained. If you want to continue using an old
miner you should use an OS of the same age.
claymore more epochs is maintained as a mod and is as good. see its link:
https://bitcointalk.org/index.php?topic=5305046.0