ClanWars not working after switching from GA

I used ClanWars plugin on GameAddict, had over 150 teams, many games and so on.
After I switched to Blackfyre it stopped working. I deleted the games and the matches, I kept only the teams in the DB. It still doesnt work.

Also import of games does not work, even though it says “successfully imported”. I am not sure where the problem is or whether it works if I delete all the current teams and let people add them again via Clan page or add them myself via admin.

Worth to mention that also the teams created using the Clan plugin are not shown in the ClanWars teams tab, although it should.

Would it help if I delete all current teams? or what would a possible solution be?