strange email

so, a couple of days ago i bought an expansion pack from a site called instant gaming, which i thought was a safe platform because 2 years ago i purchased "get to work" from there. i open ea games and i already had the game installed on my usual account in which i've been playing for like.. at least 5 years. 2 years ago, when i purchased the other expansion, i played with it but after a couple of months, a strange email appeared, it ended with ".ru",, and i've never find the expansion again, until the 14th of april, when i bought "discover university" pack. so, i go to "redeem codes", i put the code i purchased and it said that i dind't have the game installed yet, which wasn't true. i re-install it with a lot of problems and after a few hours i tried again to redeem it but again that strange email appears right under the nickname of my account, different from the one that i saw when i first tried to redeem the code. i thought it was very strange but i tried to anyway because with the work expansion worked. it said that my code had been already redeemed but the expansion in not on the add-ons section and now i'm lost because the site where i bought the code from doesnt want to give me back my money and ea games doesnt seem to recognize the code i put. please help.