Help baby refusing bottle!!

I use dr browns and my baby is suddenly not wanting it. He’s happy, not sick, everything fine and 5 months old suddenly won’t take it just isn’t interested and cries if I try to force it. Do I try a sippy cup? Different bottle? Help!! He’s having 50% of usual volume sometimes less I’m worried. Dr said “give him pedialyte to stay hydrated”.. not f-ing helpful because how do I feed

if he won’t take a bottle…. WTf please any advice I’d appreciate it