One drive shared file and folder sync issue

Thanks for the clarification. I'll double check it on those machines. My experience, having called support numerous times with our MSFT business licences, is that I've reinstalled the OneDrive sync app lots and it still happens, even with the most current version. Happened yesterday to one client. She is very annoyed at this, and I frankly can't blame her. I can't "fix" it once and for all. I'm sure it's a bug. Happens on different machines, in different tenants, with different SharePoint sites. It's widespread. Works fine for weeks, then boom, the sync is lost. Often without the user knowing it at first. It's extremely annoying. To be clear, I cannot in good faith continue to charge them for this work, as I'm seen as being a supporter of MSFT, even though I'm neutral in this. Since I can't charge for fixing the same buggy software over and over,  I'm really pushing new clients to not use SharePoint even though they are paying for it. Means higher costs to buy Dropbox or Google but I won't continue to be put in this position.