I can only get 2g..how do i get 4glte on my lg optimus L90D415 I have metro pcs and got perfect service lost my phone so using my old lg optimus L90D415 but cant get more than 2 g no matter what i do
D415, being a rather old low-end phone by nature, has no 4G support by hardware design, as indicated by the specs here.

The device does support UMTS on Band 2/4/5, and MetroPCS uses Band 2/4, so theoretically you should see 3G. However, as carriers have shifted their priorities towards LTE, 3G coverage on those bands will degenerate, especially as Band 2/4 are also primary LTE bands for the same carrier.