Catphone S61 Won't Turn on After Replacing Battery

Disassembled the phone down to the battery which is a few external screws then two internal screws. After putting in the new battery It would not power on or show that it is charging when it is plugged in. Afterward I tried the phone with the original battery but the problem persisted. It was working before but with greatly reduced battery life. I'm not sure how to begin troubleshooting from this point