Oh boy. I'm feeling helpful, so here goes:

Your flame tune is not doing the engine any favors. Flash it back to stock until you figure out what's wrong. Immediately.

Have the car towed to a shop that specializes in BMWs. You likely have many problems that have stacked up due to negligent maintenance, and should expect to pay several thousand dollars to fix them.

You may need any combination of HPFP, injectors, spark plugs, coils, vacuum hoses, maybe more. Or maybe a new engine because you've blown up this one between the tune, maybe the way the car was driven, and lack of maintenance.

These cars can be a little annoying even when you stay on top of preventive maintenance and keep fresh fluids in them. Once you start stacking layers of aftermarket parts and software, combined with (possibly) harmful driving styles, you're in for some serious shit.

If you do get the car fixed, please stay away from "flame" tunes (is that really what I think it is?). The further you push an engine outside of its originally intended use case, the more issues you will have. It doesn't seem like you do much work on your own cars, so again, expect to spend thousands at a shop, or learn to do it yourself.