I have a solution, flash orange fox and now flash rom, 1000% works
Download orange fox recovery lastest version, that is released in 2020 (this enables your STOCK ROM for ota updates released by company). Keep the orange fox recovery .img file in internal storage of your phone and flash it using TWRP. Now try to flash the rom. 100% working.
ADDITIONAL INFORMATION (IRRELEVANT)
TWRP doesn't allow us for ota updates. But orange fox do support. THERE IS PROCEDURE FOR FLASHING STOCK ROM TO ENABLE OTA UPDATES . Check the procedure in YouTube if you want.