Calf Bloat

Angus is now 12 weeks old, he looks really good and has been very healthy but yesterday evening he developed bloat. I gave him baking soda and a little veg. oil. My DH bounced his belly around until we got some good burps.

I checked on him at around 2:00 am and he was bloated again, went through the same process plus gave him yogurt and he responded well again.

I just went out and he looks bloated again. Any ideas what I can do and what we are doing wrong to cause this??

My DH is still giving him a bottle once per day just to get rid of the replacer that we have. He has free choice calf starter, calf manna, hay, grass and water.