my crepe myrtle leaves have holes between the ridges
The holes look like one per vein with no other symptoms.
Can't really tell what the problem is from that description, aside from its being a bug of some kind. Look out especially for Japanese beetles. This article has more info: https://www.gardeningknowhow.com/ornamental/trees/crepe-myrtle/crepe-myrtle-tree-problems.htm