Super hard stage of prestige didnt go through still lost stamina

I've had 4 instances were I cleared SH stage of prestige battles, then crashed right before the reward screen. It went into an infinite loop. So my only choice was to abadon the stage and guess what? It still consumed my stamina... I gained literally no points in return. Every battle was a net loss of 5k points. My lastest refinement was around 5943 or 5947.

First 3 instances I didn't fully pay attention whether there was any advance to my points. Thought that my clears went through and probably desync with server. Altho I found myself looking odd at my score. 4th time it happend, I can confirmed gained nothing yet my stamina went from 78 to 38... My connection was stable too. Earlier this morning which had most cases I was using 4G bandwith, later my own home wi-fi. I also cleared my cache few days ago.

And my placement is still between 5000-6000.