I was facing the same problem for 2 days
Tried reinstalling openmc
even downgraded to older version
still couldnt fix the problem
i even used WSL in windows to check if the problem is still present
at first it ran without any problem
but when i depleted for the 2nd time
voila
same problem again
so i scoured the forum and finally found the solution
heres the link to the comment by paulromano