Found a working sim card on the ground?

I was at an at&t store and found a sim card on the ground. Thinking it was junk I took it to use as an outline to cut my normal sim into a micro one. When I got home I popped it in my iphone just to see what would happen and it works. Data, texting, calling. I don't have data and was wondering if I can get in trouble or have my phone locked if I use the card for data until it is disabled? Or am I safe to use it?

You can't just cut a normal SIM down to size and expect it to work.

You can get introuble if someone finds out but you can cut the sim to a smaller size haha I've seen people do it

It is definetly not safe to use others sims and it will definetly lead you to some danger