Hi, I think the biggest issue is in the mix. The bass is a little too loud and not sitting well with the other elements. It’s hard to nail the mix down and depending on the reviewers set up, it could sound better or worse than you intended. But, that said, to my ears on my headphones, just normal consumer grade gaming headphones, the bass feels too loud and too present.
I would suggest trying to find a similar track to yours that has been approved and do an A/B comparison in your DAW. If you have the luxury of Izotope plugins, you might be able to measure the difference between your mix and the reference you chose.
Otherwise I think it’s a pretty unoffensive and sufficiently corporate tune. When in doubt, add whistling, hand claps and ukulele! (joking)
edit: for the record I find a lot of tracks on here are way too loud and not mixed well. My own tracks included. So don’t take my word as gospel. If it’s not a hard rejection, just try to work on the mix. If it is a hard rejection, upload it somewhere else and start writing your next pieces.
This is a numbers game and you can’t get too hung up on rejections or get too attached to a track. But what you can do, is hone your skills and perfect your craft and if they don’t like your music here, you can find other markets that might. Good luck!