stuck at “updating partition details” while installing magisk

Hi, so I have a moto 4 plus running android 7 that I am having trouble with running twrp. I am following a guide to root it by unlocking the bootloader, flashing twrp (temporarily) and then flash Magisk-v16.0.zip.

I have one identical phone (I think they have identical build number) that I can do this without any problems. The other phone that I have problem with, twrp keeps getting stuck at "updating partition details." This happens when I try to do a back up so I have to skip it and try installing magisk.zip again and it got stuck again at "updating partition details." I am afraid if I try to turn it off now I may brick the phone.

I tried asking this at the forum where I got the instruction from but had no luck getting any answer. I am hoping to receive any guidance on this matter. Many thanks!