Hello, and welcome to the forum.
Ratings/Rankings depends on many factors. The amount of deliveries, driving record, where you place in racing or competitive deliveries, side missions completed, etc. If you just started RNR, don’t expect miracles so early. If you’re not first in delivering your load, or winning races, then you won’t advance much, if at all. Racing & Competition deliveries are the fastest way to increase these statistics. Crashing, and other violations will decrease them.
Hope this helps.