Shift-F10, open diskpart and disk 0 clean, convert gpt. Reboot.
Already done that, not worked, you understood the matter, it's not the error about the MBR-GPT partition mismatch
Your partitioning is wrong, look at autounattend.xml. Setup displays a single partition equal to the entire boot disk.
I didn't do anything in the autounattend.xml, used NTL & that's created automatically via NTL while creating the ISO, & I've ben using the same settings/preset for more than 3yrs now, this is the first time getting such msg about size
I added some driver, which I usually add & added earlier as well, no issue faced earlier,
now, after receiving this msg today I exclude only 2 (heavy sizable) drivers (Intel graphics & Realtek HDA Audio) & made another ISO with the same PRESET to test, ISO size was reduced from 4.83 GB to 4.06 GB, installed without this msg pop-up
Now, making another ISO & this time excluding the Realtek HDA audio driver only, I will check it & revert here.
P.S: Earlier, in Win11 21H2 ISO, I added all the same drivers, & this msg never appeared, don't know what's wrong this time.
If you want, I can share the PRESET & the autounattend.xml