Gross, I have had that happen to me too!
When I saw it I panicked, thought I had stuffed everything up and the world had come to an end

So here is what I did!
I totally freaked out, I packed up all my tools, spent the rest of the day cleaning up the shed and the chaos around my feet and went inside to calm down and work out how I was going to stall for more time, so I could start over.
The following morning I went to my brothers panel shop to ask him about it, all he did was laugh and handed me some Low VOC clear with some hardener n stuff and advised me to just give it a nice wet coat or 2.
The rotten kid was still laughing his head off as I drove away!!!!!!
And I tell you, the little shit was right!
once the final clear had been applied I left the covers alone for hours and hours (ok, overnight in the warm shed), In the morning the marks were gone!
It was all good!
Still, I have learned to be more patient when re-masking/masking over clears or intercoat clears, give them plenty of time to dry up before working on them again.