Those USB-C to laptop power adapters are awesome. However, they can be kinda dumb. The available charge current is communicated to the laptop with a resistor, and the adapter does not change this value based on what your USB adapter can provide.

My adapter was just a tiny bit underpowered and would cut out if I tried to run a heavy CPU load while the battery was charging. I think this eventually killed the cheap adapter cable.

Just buy two