My experience with ProtonMail started off very well. I liked feeling that my email was more secure, although I wasn't sure if it really was more secure based on other things I've read. Regardless, things were fine until a few weeks in when my 2FA was no longer sending codes to my cell phone when I tried to login into my account.
So, I submitted a ticket to customer service which replied that I would receive a response in 1-2 days. Well, it's been 4 days, and there are very important emails I need to get to. I've contacted them a few more times and heard nothing. I have used many email providers, and this by far is the worst experience I've ever had. I am surprisingly disappointed with Protonmail and am changing to a new email provider.