Hi! My name is Aj and Im an Independent Advisor here to help! I get how confusing that feels, seeing the appeal approved but still cant sign in.
Since you already waited 72 hours, the best step now is to clear cache and try signing in again on both console and Xbox app. Also check your account status at https://enforcement.xbox.com/ to confirm no active suspensions remain.
If after a few more days the block still remains kindly contact Xbox support directly at https://support.xbox.com/. From there you can sign in and choose Contact Us at the bottom to get chat or call options.