Why doesn't my crept myrtle flower?

If it is planted in the shade, it won't bloom. Long stretches of hot dry weather can keep them from blooming until you get a good soaking rain. Another thing could be if you are pruning it at the wrong time. You are supposed to trim\ prune them right after they bloom, otherwise, you are cutting off the parts the blooms are forming in. I hope this helps.

Late Pruning: This is by far the most common reason for crape myrtle blooming problems. Crape myrtlesshould be pruned either after they finish blooming, or in very early spring before they sprout. Don't prune them once they've started growing in spring, because those new shoots give rise to this year's blooms.

https://www.todayshomeowner.com/why-arent-my-crape-myrtles-blooming/