Sometimes I have to wait for a long time for sync to take place. I’ve noticed that if I mark a x on todo item (- [x]), total count of characters is not changed and no sync takes place. If I type a character and then save, the sync happens.
Sometimes I made changes on Drafts on Mac, and content of the same draft in Drafts on iPhone didn’t change after a long time. However if I look into versions of this draft on iPhone, I can see versions from Mac are already there. Even worse, sometimes new version on Mac got replaced by old version on iPhone after I open Drafts app on iPhone.
Probably best to report sync issues to the support mailbox. Often it needs logs and tests to track down why an individual is having issues.