Need some advice

First off I've been stage 1 giac for a few months now and just yesterday I started have issues. Car threw cel for low fuel pressure. Car feels like it chokes out after 3500 rpm. Took it to the dealer they say hpfp is running fine but my car is running lean. Any ideas where to go from here?

did the check the lpfp?

They said everything checked out to oem specs.. thinking bout flashing back to stock and seeing if it persists and going to a different dealer since I'm still und we warranty