Very strange indeed, which version of twrp are you using? And did you check the MD5?
I installed this build twice to 2 different devices prior to upload.
About to go to sleep so check the md5 , if it matches, full wipe & try again, if it fails, restore your backup & I will take a look tomorrow evening..
Love how quick backup and restore is in this beast.
Edit: I am running a slightly modified version of twrp, link below but as always, use at your own risk. Team win and all affiliates will not be held responsible
EDIT: I wonder if people are using the version from the website and not the beta version I posted in the thread . . .