Thank you for being a part of Samsung community. We would like to inform you that kindly download the face widget theme from theme store after that u will be able to apply face widget theme on AOD. Settings > Lock screen > Always On Display > Display mode > Show always. If issue still persists, KIndly provide logs/video within 15 minutes of issue occurrence by registering this feedback via Samsung member application i.e. Samsung member BETA app> BETA feedback>Sendfeedback>Error report>Collect log files>attach. Be sure to hit ♡ when you find an answer that works for you. For Further assistance, you also connect us via Samsung Members web community by following mentioned url https://community.samsungmembers.com/en_IN#/
