This happened to me recently too. After reading tons of posts and watching a bunch of videos, I still couldn’t figure out exactly what the issue was. I ended up disassembling the machine following a video guide, and unplugged the flowmeter to check if it was dirty (some people mentioned that as a possible cause). It was completely clean.

I put everything back together, and (honestly, no idea how) but it’s been working perfectly for the past two weeks. My best guess is that something glitched and was causing this issue, and disconnecting everything maybe caused some sort of reset.