Blueberries are woodland edge plants and like some shade and a moist compost or soil though they'll cope with full sun if kept moist at their feet.
I once left a pair of mine in pots in the care of a teenage neighbour who did not understand the concept of thorough watering despite instructions and I came home after two weeks to find both fried to a crisp. After copious watering, and a dose of liquid tomato food they recovered but I had to prune out a lot of dead stuff. I now have them planted out in big 80cm wide and 60cm deep holes filled with ericaceous compost and they get a good ericaceous feed every spring. They're doing fine.
Move yours to shade and try watering them thoroughly enough to soak their compost and then let them drain but keep them moist thereafter. If it doesn't work, you'll not have lost anything.