If your school use Microsoft, Google or Apple for your email, you can use the "Sign in with" buttons. No emails are needed and filtering issues are avoided.
Key Information:
The SPF and DKIM authentication checks had been configured will satisfy most email filters that the PIN email is genuine. However, there are other factors outside our direct control which may cause aggressive spam filter settings to reject these emails.
Check the server-level filter policy.
The admin for your school email service will need to check this.
The above email address (or the domain 23equations.app) needs to be added to the "Safe Senders" or "Approved Senders" list.
Methods for doing this are well documented but the exact method will depend upon the service provider you use and also the service level of your contract.
Please contact us if you have any further questions.