Look at the list of not synchronized items and determine, whether they are actually missing on device B (probably not). If they are not missing, you can restart syncthing with the -reset-deltas option and see whether the problem goes away then.
And in general if you have a support request: Please include as many relevant info as possible, at the minimum used syncthing version, which platform you use and probably more. A full screenshot already contains that information as well as metadata from the folders in question, so that’s always a good thing to include (you can always black out sections you don’t want to make public and are irrelevant to the problem).