Messages not syncing between my iPad, iPhone, and Macbook - Again!

This has been going on for a couple of years. Messages are not syncing between my devices. It's frustrating as ****. I have done all the usual, obvious, and suggested solutions. Nothing seems to be a permanent fix. I am from an older generation in which "glitch" was not a common term, and I am used to machines working all the time except for an unexpected breakdown. The digital generation might shrug their shoulders at glitches. Us older academics get frustrated. What does this community recommend? Thank you.