Fetching errors for notes

i’m using a free opsone.ch account (with 2fa) for notes and tasks in the latest firefox…
for some reason i get many erorrs often…
Screenshot from 2022-06-12 18-27-40

i’ve added a screenshot of the most common errors
can you tell me what can i do to fix this?
do you recommend OPSONE?

i don’t like services like notion or evernote so i would really be glad if you help me to solve this…