Help please!

Ok ya’ll i need advice. I have a 2012 Mazda 3 that started misfiring. We’ve changed out all the coils and spark plugs and the plugs were gapped correctly. Car feels “heavy” when driving and i had another misfire within a 10 minute drive at 35mph. I ordered some Liqui Molly to clean the fuel injectors.

I need to know where to go after that. Car has about 170k on it, mostly highway miles.