Are you saying that twrp doesn't see magisk.zip located in internal storage?I have a problem and I didnt see anybody with the same problem. Im on F73 version, I patched my boot.img, and when I want to temporarily boot the patched boot.img, it works ok so phone reboots but in the middle of the process it reboots again, so when I try to enter Magisk app and direct intall, I cant becuase that option is gone. I am not able to root the phone. (I was rooted in A11 and I updated my phone with successives OTAs until last one that was F73, so I wanted to gain root again following the initial way).
I also tried booting twrp and flashing magisk.zip but twrp said that there was nothing in my internal memory. I dont know what else to try
Thanks in advance.