Shift problem

Robert are you saying the problem just seems to be 1st and 2nd gear but 2nd to 3rd shift works ok? If so it sounds like the 1-2 shift valve is stuck in the valve body. Might even be a broken spring on the valve. Maybe try putting some trans additive in it such as K&W Trans-X. It might free it up if it's just stuck. If it don't you'll have to drop the pan and valve body and take it apart and give it a good cleaning and or replace the spring.