Hiunday Santamo year 2004 works in 2 cylinders

Hey guys. I'll tell you about this Hyundai that came into the shop with this problem. They had already replaced the ignition coils and even the ECU. I'm really worried about the ignition module; I don't know if they replaced it, and the owner doesn't know either.
I've checked everywhere, and I doubt it's a broken wire—they don't look damaged. There's no signal to either of the two injectors, and the cylinders themselves aren't getting spark either. We scanned it, and it showed a problem with the coil, but it's new. I reversed the coil's connection, and now there's spark in those cylinders and a signal to the injectors. I hadn't mentioned which part, but it's the problem with two cylinders. I'd like to know if anyone has experienced the same thing or if there's a specific manual for this model that could help diagnose the problem. If I find the problem, I'll definitely let you know because it hasn't been easy. Cheers.

Hello everyone, . greetings.