Hello, @danolenors
I'm sorry for the loss of your LastPass Notes there.
In this case I would suggest first clearing your LastPass cache:
If that has no effect, please remove the LastPass browser app completely, before re-installing again, and logging back in with your account credentials.
If I remove the extension and add it again. Will I lose my passwords and notes?
I have the same issue. my notes are gone and I did not delete them.