need ideas about weird stalling issue

So my bike (2008 Polaris Sportsman HO EFI) was running fine, it had been sitting up for a month or so so I started it up and just let it idle for a good while. When I came back the engine had stopped. And now!…

It is hard to start but it will if I give it a little throttle but it immediately starts bogging/stalling and I can’t get it to keep running unless I continuously pump the throttle.

If I just lay down on the throttle it stalls and quits.
It I don’t give it any throttle it might idle a while, sputter, misfire, and quit.
If I pump the throttle on and off it goes into a cycle of revving up / bogging down. I can keep this thing going for a while like this. I can even drive it around at really low speeds like this, but I can’t really get it up to any sort of speed because it bogs down more than it revvs up.

What do you guys think? What can I check? I’ve looked around for these sort of symptoms but I haven’t seen anything that is prevalent.

Thanks,

Chris