ProtonMail is a simple, secure, and easy-to-use email service. All the messages that you receive and send using ProtonMail are secured with a built-in end-to-end encryption feature. In this section, you will see some of the common Protonmail issues & login problems and their solutions.
Before you use the Safari web browser to sign in, check if it is set to Private Mode it help to fix the Protonmail issues.
If so, disable or change it to some other mode.
Note 1: ProtonMail does not work with Safari’s Private mode.
Note 2: Usually, in some Mac computers, the Safari browser is set to Private mode by default.