Samsung - Samsung fe network problem

It is almost * months i purchased this phone and i am facing network issue every single time i play games and upload youtube content .samsung claims it *g but it cant capture network properly it makes me angry while playing games because the network is so poor
Cant use * sims together for this reason .i thought it would be a good phone and wasted my ***** on it .i was waiting if samsung could solve this problem but it is now couple of months and samsung always ignores its customer so .. i want a latest samung phone s** ultra where there is a hope of good network and it does not get me angry while playing games and uploading content