Solved How to avoid e-mail notifications also for my posts

Thanks for the reply, are you on the latest v6 version?
if so can you implement this PR I did (this change will be in next version).
if you can do it manually the we are on the same code so that would make it easier to explain / troubleshoot.
github.com/Kunena/Kunena-Forum/pull/9407/files

I've done lots of tests.

1) In a clean Joomla 4.3.1 + the latest Kunena installations on the same server, and with the same Kunena settings like in the website where I have problems, I don't have any issue. I don't get email notifications for my posts, even in subscribed categories.

2) If I link the clean J4 and latest kunena installations to my current website DB (the one where I problems), I still have the issues.

3) If I copy, in clean J4 and latest kunena installations DB, just the Joomla users DB tables of my current site, everything works fine, and I don't have any problems, 

I think that something went wrong when I upgraded from  Kunena 5 to Kunena 6 (and from J3 to J4), and now there are some DB table in my current live website, probably related to kunena, that have issues. 

Now, the goal would be to understand which ones. Any suggestions?  

I found the tables responsible of the problem....

I substituted the "kunena_user_categories" and "kunena_user_topics" table in my current site, with some new ones taken from new kunena installation, and I solved. Now, email notifications work as expected.