I need fresh corn tortilla advice

I made tortillas for the first time the other day. I didn’t have any Masa Harina so I used Pan. They came out terrific, almost like a thin chalupa shell. Absolutely delicious. Then a couple days ago I tried to do it again, but this time I used Masa Harina. They all just fell apart. Nothing would hold up, and even the fried bits didn’t taste great. What is happen here? What’s my next step?