I've been using Tixati v2.34

I've been torrenting many things (about 100 total torrents, but only 5 at a time) for a long time now and every month, the torrent passes expire, so I have to go back to the site and acquire new torrent meta-files for that specific month.

I load the meta-files in Tixati and I'm greeted with the usual "Loaded Duplicate Transfers" window that prompts me to merge the existing transfers. I click "Yes", but nothing happens. The tracker is not updated and no new trackers are added. If I delete all of my outdated trackers and merge trackers from the new meta-file, the trackers window remains completely empty. I've tried this with as many as 80 different torrents and the results are the same. Most all of my torrents come from the same site, but Tixati v2.34 is whitelisted there and this was never a problem 2 or 3 months ago on whatever version I was using then.

To be absolutely sure it wasn't a problem with the site that provides the meta-files, I tested this using random torrents from 2 other sites and the problem persists.

If I remove the torrent (and not delete the local files) and then load the new meta-file, the torrents starts, spends a lot of times checking, and finally picks up where it left off. In this way, I accomplish my goal, but it is inconvenient that merging trackers doesn't work and I instead have to go through a long process of removing torrents and checking/waiting to check.

This is a known problem. It will be fixed in the next release. And it is fixed in the alpha that is testing right now. You can go to https://testing.tixati.com  to get the fix now and help alpha test, or wait for the next release.