you can get lte phones from sammy and lg for vm for as little as $70 on sale. So, your current ancient phone could be the problem. Another reason is they are doing new vision upgrades on nearby towers in your general area.
from experience, i prefer LG and Htc phones over sammy, due to better features and quality control.
back when i was under vzw contract, sammy phones were nothing but trouble compared to lg, casio, pantech, and motorola. Nothing much changed for me with smartphoes and prepaid except getting much more for a lot less expense.
