Thanks for ur reply 

I checked it and dataset looks right (it’s well-balanced and also I added oversampling to be sure that in every batch number of elements in every class will be the same)
I checked it too and loss function looks very well actually. It starts from ~0.08 (after first epoch) and stabilize after ~80 epochs to ~0.0005.
I make validation after very epoch of training so how can I make it sooner?

What’s about my code? Maybe there is some stupid mistake but I didn’t catch it?
Maybe any others idea what I should to check?