Thanks for reaching out – have you tried uninstalling & reinstalling the app? Also, check the "Double tap to seek" settings: tap the icon on the upper right side of the app > Settings > Double tap to seek, then choose a setting. Keep us posted!
Hmm, that's odd. We haven't received any reports about this. Can you also send a feedback report by following these steps: https://yt.be/help/feedback ? This helps us identify and fix possible widespread issues.