I’m having the same problem. Today I tested my contact form and while I received contact emails after changing my email address a few weeks ago, today, nothing happens.
I tried sending an email from the same personal account I was using as my email address in my test of contact forms and it worked great. However, when I test using contact forms, I don’t receive the email. I’m using a Google business account, so suspect whatever the problem is with GMail is the same one I’m experiencing.
I’m no guru, so unlike szymon.v, I can’t tell you whether the code is messed up or not.