Additional terms under GNU AGPL version 3 section 7.3(b) and 13.1:

If you have included SFTPGo so that it is offered through any network
interactions, including by means of an external user interface, or
any other integration, even without modifying its source code and then
SFTPGo is partially, fully or optionally configured via your frontend,
you must provide reasonable but clear attribution to the SFTPGo project
and its author(s), not imply any endorsement by or affiliation with the
SFTPGo project, and you must prominently offer all users interacting
with it remotely through a computer network an opportunity to receive
the Corresponding Source of the SFTPGo version you include by providing
a link to the Corresponding Source in the SFTPGo source code repository.