Help with adding LTE bands

Alright I can't post links as I'm from my phone but I tried adding American lte bands to my D802, i tried calculating those numbers you need to write to the chip and also tried it with the number that turns everything on but with both tries I still only get refarmed 4G which sucks.

I can't buy a new phone but I want LTE and thought that you can add bands to Snapdragon chipsets.
If anyone could help me or enlighten me I would appreciate it alot.

Thanks in advance.