This seems to be a bug in the slicer. I’m seeing the same issue in OrcaSlicer if the skirt height is set to more than one layer (even if the skirt is disabled). This makes sense if a skirt is used (can’t print a continuous spiral if you have to switch between printing the object and the skirt), but not if it’s disabled.
What slicer are you using? If it’s a PrusaSlicer fork, this is likely the same bug.
You can use a boost converter to boost the 5V of an USB port to the 19V your notebook needs.
Assuming 5A output from a powerbank (which is probably about the max you will get without USB PD), you could theoretically get 0.55A at 19V. With the unavoidable inefficiencies, you will get less.
So, maybe enough to very slowly charge your notebook while it’s off. But when it’s turned on, the battery charge will still drop.