I have both swedish and english activated in GBoard, but I'm using the swedish layout so I get easy access to the letter å ä ö.
My problem is that Gboard doesn't seem to "learn" some new words. A specific example is when I'm swiping hon (swedish for her), it never suggests hon, instead it autocorrects it to jobb (swedish for work) every single time. I've erased the suggestion, I've typed h o n manually and clicked it in the top bar - I even added hon to my personal dictionary in the Gboard settings, but nothing seems to help.
It's gotten so ridiculous that I just stopped erasing and correcting it when texting some of my friends, I just informed them that if they see an oddly placed jobb, just assume I mean hon :)
On a side note - both me and one of my friends (who's using Sony's built in keyboard) seem to experience periods of our predictions going haywire and suggesting completely wrong words, or in my case often weird acronyms like DF, DT, DGV etc. This seems to last for a few days and then it gets better for few weeks. Might just be coincidental, but I'm curious if anyone else is experiencing something similar?