A small correction, the above commands disable OTP globally and gray-out OTP user’s settings, if I’m not mistaken. Same as admin can do from WebTop system properties.
As admin, from Domains > NethServer > Users you can right-click on a user and select Settings from context menu, then access user’s OTP settings and deactivate it for that user.
To disable OTP for a specific user (or the admin), from the command line:
su - postgres -c 'psql webtop5'
UPDATE "core"."user_settings" SET "value"='false' WHERE "key"='otp.enabled' AND "user_id"='theusergoeshere';
No signal-event required.
Later on, either the user or the admin can reconfigure OTP settings.