Breastfeeding question

Al

Bit of a question guys. Breastfeeding my 3.5 week old boy, but with a bit of hypoallergenic formula too as he was diagnosed with CMPA (long story).

Had a frustrating day/night. He’ll root, so I’ll try him at the boob, he’ll be on for a min or two and then stop/fall asleep. I’ll move him to his moses basket and he’ll immediately wake up/thrash his arms & legs, so I’ll move him back to the boob, he’ll try/fall asleep, and repeat over and over and over. Only way to get out of this non-productive cycle is to give him a bottle it seems, which wakes him up, he chugs, and then he’s out.

Has anyone got any suggestions to get him to actually boob? Been up since 4am just picking him up, putting him down, picking him up, putting him down, etc.

Thanks! :)