There is no such thing as 2 matching sets of 2 sticks, they were not QA’d to run together and are not guaranteed to run at advertised speeds when you mix 2 different kits even if they are packaged as the same SKU/timings.

It is not “growing” pains, this is literally what ram manufacturer’s will tell you and is how it is been since before xmp profiles were even a thing in the DDR3 days.

Unless you have a quad channel kit/mobo then this is a lie (and I’d bet money you don’t).

Only single kits of ram are “guaranteed” to work at advertised speeds. If you are going for overclocked RAM for gaming performance you should only ever be buying a single kit of ram (if you want 64GB then you should get 2x32GB not two different 2x16GB kits). Probably an expensive lesson this time around but short of returning your ram and buying a proper single kit of dual-channel ram no there is no “workaround”.