@Rhea presumably you have Queal 4.0 bags?
I've noticed a difference in oat powder "hardness" between Queal versions. Real or not. Probably in the 3.x to 4.0 upgrade. I assumed we were getting more whole fibers in the upgrade, but after being used to the drink-like 3.x, the 4.0 hardness was an initial surprise. Maybe 5.0 was suggested or rumored to be more smooth again.
I know of a trick which might help if you anyway have pains in your throat. You could warm up water to somewhere 20-30 degrees, probably keep it several degrees below body temperature, mix well, and let the mix sit for 2-3 minutes. A sitting queal 4.0 mix get some sediments at the bottom.
I shake the shaker forcefully to not be left with the (presumably whole grain bigger pieces) in the end since they can be hard to swallow even mixed with water - and I really like whole grain oats.
In your case you might actually want to let the harder oat sediment down and leave it at the bottom, and if you're in need of fibers you can get it from some other foodstuff.
I once tried "cooking" queal like you'd cook morning porridge. Winter, and tap water was cold, but left it too long on the stove. I didn't try that variant again... but did pre-mix water to nice temp in shaker a few times that winter.
Also heating above 30 degrees starts "killing" vitamins.