Question [Q] Bandwidth in Automatic is not working

Hi experts

I have a new LG G Flex LG-D958 in Brazil and basically I have 4G working in my home with full signal, but if I move to a place where there is no 4G, (only Edge) the band will never go back to 4G automatically, even when I move back to a place where the 4G signal is full. Is like my phone goes down in the bandwidth but never goes up again.
I have to manually go to config the Network Mode and change from Automatic to 3G, and then Automatic once again to make it works back in 4G.

Is there a correction for it? Sounds like a issue with the Baseband. Is there a software or something I can install to make the phone try to move from EDGE to 3G/4G automatically?

Thanks experts.
Daniel Viana