Question FTP is set to read only

[Bod]

Server operating system version

Debian 12.5

Plesk version and microupdate number

Version 18.0.60

We have created an FTP account and it connects fine.
Using the FTP account, we can see all the files and read the files but cannot modify them.

What else do we need to do to give this account write permission?

 

[Bod]

For further information, I have checked proftpd.conf and the FTP group is set as psacln
I've also checked the FTP user I created and they are in that group...