Inside out and no dryer.
You have two possible things you can learn from this. The quality of the shirt was shit, or your personal style of washing your clothes is/was wrong. The solution for the first one is buy better clothing with different printing technique, for the second one try washing it inside out, with less temperature and maybe with less aggressive laundry detergent. I have some low quality shirts that also had this problem (but just after a few years) and i have some i had for a long time without any sign of age. Of course it's not always easy, especially if you buy a lot of stuff online, you can't quality check that stuff there, but generally a nice print is definetly possible without going lost after a few runs trough the washing machine. Or, a different approach, don't buy prints :D Most of my newer stuff is without any, and made interesting by cuts, material and colours, not by symbols. Also works, but that's definetly a choice of taste without any right or wrong.
Don't use a dryer for those.
If your shirt had plastisol printed shit on it then it wasn't cool in the first place
only thing i could recommend is turning shirt inside out, with a big load of laundry, then air-dry instead of using the dryer
Check how much temperatur the shirts can be washed with. And get shirts with better print quality, cheap ones get damaged easier.
Buy simple clothes and save money
Got this one shirt I've owned for 10 years and it used to have a design on it
Don't buy heat printed shirts you knobhead.