Anyone worked this out?

So I have DSPD but my sleep is polyphasic , I wake up prematurely tired about 4.5 hours sleep and then can't sleep for another few hours then even then I wake up prematurely after about 2 hours and need about an extra hour to feel okay (which I don't always ) It's very debilitating , I can't sleep for longer durations and basically spend 90 percent of the day tired/sleep deprived

Has anyone had any joy merging their sleep? Or had similar problems?