According to the XP your character has (2700) it is only a level 4 character - but you have 5 class levels (4 Druid + 1 Barbarian). This is what is causing the problem.
Either you haven't added the XP you should have - or you have jumped the gun and added a class level that you shouldn't have.
Made a Moon Druid 4/ Barb 1, proficiency bonus shows +2 instead of +3.
Show a sharable link of the character in question so we can see?
Here you go.
According to the XP your character has (2700) it is only a level 4 character - but you have 5 class levels (4 Druid + 1 Barbarian). This is what is causing the problem.
Either you haven't added the XP you should have - or you have jumped the gun and added a class level that you shouldn't have.