Rules for Samba Share password

I just spent ages and ages trying to connect to samba on my RP4 running home assistant and the Samba Share add on. Everything looked correct and I tried to connect with both my computer and my phone. Never worked.
Then I changed only my password to “12345” with the quotation marks and it works. In the guided I watched they didn’t seem to have to create a string.
Obviously I’m not going to leave it as that. Are there characters I have to avoid? Is there a limit to how many characters it can be? Are the quotation marks compulsory? Googling for these rules is not being helpful. I think maybe there is a seperate rule for that Samba add on.