forerunner 245 not charging

Cleaning the contacts on the watch (using isopropyl alcohol) seems to fix this. But. What I’ve learned is that once you start having to do this, you KEEP having to do it. I have to do it every second or third charge. I didn’t run into this until after I’d been using the watch for over a year. But now the cleaning is a regular requirement. When you charge, check the charging status (press & hold the LH middle button) and check for the lightning bolt. But even THEN, the watch may not actually be charging, and the only way to know is to check the percent charge after several minutes to see if it’s increasing.  If not, go back & clean some more, and try again.  I’m wondering if some kind of transfer buildup occurs on the contacts in the charging CABLE, as well as the ones on the watch, complicating the problem.