Well it sounds like your getting fuel, spark, air, so the only thing left is compression
Like I said chinese knock off engines have been known to randomly lose compression while running, what will happen is they lose compression while running, but will still run, and not start when you stop running and go to restert it. Ive had it happen to me plenty of times, you then replace the crap chinese parts with oe parts and your good to go
take it to a small engine shop and have them look ar it if you cant get it started, they use that engine on tone of lawn equipment, like chainsaws, leaf blowers, vaccums, roto tillers, etc so they should be able to tell you whats up