16’ Wrangler Misfire Issues

Hello - I was driving my jeep on the highway last week when the engine started running rough and my engine light started flashing. I took it into the shop last week and they told me they weren’t able to get it to misfire for them, so they did a tune up and replaced all spark plugs (it needed it anyway, have 160k miles on them). The engine light turned off and it was running great, I’ve put about 200 highway miles on it since. Yesterday, I was driving it fine and stopped to get gas. I filled it up and as soon as I let the gas station, I could feel the engine running rough again and shortly after my engine light flashed on again. I was able to get home keeping it under 50 mph to keep the engine light from flashing…any thoughts on what could be causing this?