SELLER’S TRN field is locked (read-only)

I am facing an issue in the ZATCA eInvoice Phase I
I need to update the Tax Registration Number, but the SELLER’S TRN field is locked (read-only) by the system and does not accept any manual input.

Could you please advise on how to update this number correctly? Does it need to be modified from the main Company Settings/Profile to reflect here automatically, or are there specific user permissions I need to enable?

Thank you in advance for your assistance.

Goto Settings-Business Details,click Reset button.
This should work,
QR generator page will ask you to enter TRN.