@Omarvalenzuela: Did you recently complete a software update on your S21? If so, have you tried checking for any updates for WhatsApp via the Google Play Store? If it's up to date, please try heading to Settings > Apps > WhatsApp > Force Stop > Storage > Clear Cache.
I am having this problem too and it is affecting my work big time! Almost wanting to go to Att and change to an Iphone. New update not compatible with Whatsapp AND Ishot! I have ALREADY TRIED everything Samsung and Whatsapp suggest to fix. Can I go back to older versions. W/out compatibility with these 2 apps, this cell sucks!