taste burnt

So i recently bought the tfv12 and everything was going great. this morning i came to the conclusion i am low on juice so this younger kid offers to fill my tank for 2$... not thinking about it he fills it's all the way and once i hit it it was the nastiest taste i've ever expierence... i tried...

I Have Had Several UWELL Crown Tanks. Out Of Nowhere It Started Tasting Burnt No Matter Which Mod I Use Or Whether I Use . 25 Or. 5 Coils. I Turned The Voltage Down, Tried Turning It Back Up, Gone Through A Bunch Of Coils But It Still Does It. Any Advice?