Hi mate, can’t guarantee anything but try the following:
1. From the ‘SETTINGS’ page where you see ‘PERSONAL INFORMATION’
click the ‘MAN CITY’ tab in the top left hand corner.
Now click the icon (top right) & select ‘LOGOUT‘. Once logged out, click the same icon & log back in from the ‘Sign In’ page with email & password.
From the same icon select ‘MY ACCOUNT’ from the drop down.
Is there a supporter number there now in the grey panel below his name?
If not, make a change to one of the fields in ‘PERSONAL INFORMATION’ then save that change. (change something in the address, town, street etc).
Now log out as above, then log back in.
2. If this doesn’t work try to add him to your ‘Friends & Family’ on your account using ‘Last name’ & ‘Postcode’ after you’ve clicked ‘Create a Relationship’.
3. If there’s still no supporter number been assigned the only options left are contacting supporter services
mancity@mancity.com
or 0161 444 1894, opt1, opt2, opt1
Hope this helps.