Earlier quoted context omitted.
That probably won't help much since OP said they aren't even using 14GB of VRAM. I have dual GPUs and use the 2nd one (3060 Ti with no monitors connected) for rendering, which is nice because I have the full 8GB free.
I was looking at GPU graphs and neglected my physical RAM. This machine only has 32G and I didn't notice I was hitting a ceiling on memory allocations too - I took the error message about GPU memory allocations at face value. I bumped my system commit cap (increased paging file size) by 24G and now I can use all my VRAM.
I'm doing 576x576 on my 3060 Ti - just wondering the max resolution you can render now using all your VRAM?