What is your location and what has been the high temperatures these past few days? Did you tell the tech you have set your thermostat to 65 degrees in past summers?

Is your warranty for parts only or did it also include labor?

You should do periodic preventive maintenance. On a new unit every 2 years should be sufficient. This requires opening the condenser, doing a thorough inspection of all internal components, measuring voltages, and hooking up gauges to measure the refrigerant level. You might call it a "tune up".

Spraying the condenser with a hose to clean the coil of any debris is part of the maintenance. I would expect to pay more than $65 for a thorough preventive maintenance service.

Mike pretty much covered what can be covered without inspecting unit. It sound's like your contractor doen't know or possibly care what he's doing. Call someone else and there's no need to discuss prior service call.

Need to check delta t and your supply temps at inside registers...post back...

The dial on the thermostat does not determine how much or how little cooling you get. There is a maximum that depends on a variety of factors typically the size of the load being placed on the structure.

If the load is light: like 85 degrees out side you could achieve 65 degrees indoors if everything is operating as it should be.

20 degrees from OAT is all you are going to get.* (*Depending on design and location not to mention proper operation of the system.)

The OAT will vary through out the day as well as the year so it's not hard when shooting for these outer limit thresholds to find the maximum cooling you will get.

There are design limits. You can't just set a number and expect to reach it. Air conditioning has NEVER worked this way.

This doesn't mean there isn't a capacity related problem with your system. Stop using maintenance men as a service provider.

Old house, 2nd floor is hot. This is typical. You need to start looking at more attic insulation, perhaps better windows as well. If your roof rafters are your ceiling in the 2nd floor then the rafter joist space needs insulation installed if there is none, or better insulation like closed cell spray foam if you have fiberglass batt.

Otherwise, concerning the AC, if it worked ok last year and is not this year then you are probably low on refrigerant. Very odd the HVAC tech that came out did not check that. From the sounds of it, he couldn't care less. Although setting below 70 is usually not needed. You probably have the thermostat on the main floor and the 2nd floor is still hot so you try to set the AC lower, that is probably what is going on. So there is a ductwork design problem, your not getting the airflow needed to cool the 2nd floor enough. Add that to the old house insulation and old windows and yea its going to be hot on the 2nd floor while the sun beats down on the roof and turns the 2nd floor into an oven.

If you have an attic above the 2nd floor that would be fantastic because you have more options at your disposal. Easier to add more insulation, easier to add ventilation to the attic to cool it down. Still need better ductwork design for 2nd floor.

Less invasive option is a window unit upstairs. Less efficient and higher energy bill. But first you should start by getting the refrigerant levels checked in your current unit by someone competent.