I got 2 rejections for OBDII EGR, EVAP SYSTEM, and HEATED O2 not ready. Why? on 1999 Chevrolet Blazer

I just completed an oil change, changed my oil filter, air filter, spark plugs, and wires I also changed my gas cap because my check engine light was on, my mechanic reset and told me to do the drive cycle, which I did but still not ready with those three things I listed above. My registration is up in 2 days please help

Asked by for the 1999 Chevrolet Blazer
What steps did you do to do the drive cycle?
Typically, if the monitors are not complete, it means the drive cycle has not been run. Could be there is a fault that has not turned on the check engine light, or your computer is not seeing the right conditions to run the drive cycle.
2 more answers
I agree, some vehicles have somewhat "wild" drive cycle requirements and they can sometimes be difficult to accomplish in limited diving situations. Try both highway and city driving, and if it still doesn't reset see if your technician can look up the requirements for you.
A couple of simple things come to mind. Engine temp should be in operating range middle of gauge, gas tank needs to be above a quarter tank and below 3 quarters. Do city and highway driving . If this fails get a copy of the factory recommended drive cycle