FTP Access icon available when logged in as owner of subscription.
If login to subscription as admin icon is shown and additional ftp users are persist.
Additional ftp users do not persist on web service node
After additional ftp users were created Service template was changed/updated on the another one with disabled parameter Additional FTP accounts management.
To fix the issue please perform the following steps:
Go to Service Template > Parameters tab > Edit
set Additional FTPaccounts management to true.
Go to Service Template > General tab
Click to Apply Template Limits and Parameters
On the management node run the follwoing command:
/usr/local/psa/bin/repair --reconfigure-ftp-site -webspace-name domain.tld