How can i keep my mana system from going past a growing maximum?

as the title says i made a mana system with variables already have a working overlay and such but i wanna ask if there is a better way to keep it from going past the max which ive used another variable for currently it kinda bugs out for a few seconds spamming the number a bit over and back down for a few seconds before stopping any way i can fix that? also is there any way i can make the regen system better? ty in advance 

here's the procedure to keep it below max

Here is the mana regen system