Misfire that won't go away, anyone tried a specialist for engine repair?

[valentinestaveley]

I've got a 2013 328i that's been misfiring on cylinder 3 for about a month now. I've replaced the coil, the plug, and even swapped injectors around but the code keeps coming back. I'm not a mechanic, just someone who watches too many YouTube videos and thought I could save a few dirhams. Now I'm stuck because the car runs rough at idle and I'm worried I'm doing damage every time I drive it. A guy at the parts shop told me I should stop guessing and find a proper BMW shop, and he mentioned that some people in the community talk about bmw-garage.ae/engine-repair as a resource. I haven't called them yet, wanted to see if anyone here has actually used them or knows someone who did. Did they fix a stubborn misfire for you? And how much did the diagnosis run you? I'm trying not to spend a fortune but at this point I just want it running right. Any advice would be great.