Hello! My name is Matt! I currently work for an HVAC company. Had a question about a residencial forced hot air oil burning furnace. The burner is working just fine but is not heating the entire home properly. There is one room in the house, the master bedroom, and a small bathroom that need to be heated much better. Any thoughts on what can be wrong?

Let me ask, if you work for a HVAC company why are you asking for help? Normally the best answers on this post are from current or retired HVAC people.
The bedroom and bath are probably at the end of a duck. The air has cooled a bit and the pressure has drop so there is little volume. I'd try an after market duct booster fan.