I just got fairly use infinix hot4 like 4 days ago due to the hype about the battery,but so far have not been enjoying the so call battery at all,i mean its doesn't even last up to 6 hours on usage(not heavy usage). I need ur candid advice people on what to do

I bought use infinix hot x507, the phones does not switch to 3G, all prefered networks are all 2G, even after i changet it in developer options, it still remains the same