I am also experiencing this problem. I'm trying to upgrade my Divine Speed boots to level 12 but they're stuck at level 10 despite "Success" happening multiple times. I wasted over 100k silver trying to investigate this issue.

Don't feel bad, I just wasted 3 million trying to upgrade 12 to 16 on "Relentless" artifacts. Dispite getting "Success", 3 times, it's stuck at 12.

Sucks that it even takes that much damn silver to upgrade just 3 fuckin levels. Fuck you, Plarium bitches!

The more you progress in this game, the more flaws you find. The damn game just isn't fun anymore, in specific areas... Almost worthless. This game use to be a nice time killer, and fun. Now it just sucks. They keep adding more crap and they haven't even put their so called, "Technomancers", to work to fix anything yet. What the hell do they do? 

I haven't seen anyones "reported game bugs" get fixed yet, like the link to "Bug Reports" says in the description.

This game is just another bull shit money maker. Luckily I know about the game rigs and I sure as hell won't spend another dollar on this shit. I stopped buying your crap a while ago. And for anyone else that wants to know, make sure you all are recording your battles. Lots of stuff happening all at 1 time in battles. Not everything works as they say it should. Barely notice it sometimes.

Anyways. Upgrading artifacts is screwed up too now. Someone fix this crap please. Fuckin lazy asses.