UMI TouchX went totally dead after 6 month

GTEKES

I bought a UMI TouchX Nov 2016.  As battery was getting really hot, I contatcted the reseller (He stopped working with UMI now). The Amazon seller offered to send me a new battery, I never received. Now, after 6 month, phone is 100% dead.
As I was reallocated to Brazil sending the fone to China and waiting for a repalcement would take over 3 month + P&H costs & 60% import tax over the new phone, not worse the trouble.

Please advise what to do.

I really loved the advanced configuration of the UMI cellphones, but the customer service by now ids 0.0  No contact e-mail, no hotline, just the forum where I never received any repply by now!!