Captive Portal with Email Collecction and OTP?

[WULABDoog]

Good day all.

I have been able to setup captive portal with email collection using FAP and FGT, but now, due to "security" stuff. I need to change the mode from email collection to something with OTP.

Does anyone knows a guide or where can I find information on how to setup the captive portal so the Fortigate sends OTP to the email using email collection?

Like, a client comes to the site, connects to the wifi, and from there I want the fgt to send an otp so the client can login.

or this kind of setup is too complicated and I should look towaards using authentication with otp only?