error message in email confirmation from Membership 2 Pro

I installed this plugin and I'm testing it out. So I logged out of my admin account on Wordpress and went to the site in a different browser. I created my account and received the email confirmation link. All good so far. I clicked on the link in my email, which was:

https://u3453434.ct.sendgrid.net/wf/click?upn=riAx9h3XqwchJcuAPw8wd-2FkiWYydQ5z-2B-2FFEYiXWEw-2BuuPZSsly7bSww9eXhnuC-2FQCR-2B-2FhXz5-2BGxiaNBKeZjVhC-2BJuex5j-2BtzeGlSOy7hi08E1YghPpeoH7Co0ZQz9JXASnArC7roG0u3UJ-2Bsw77QPQ-3D-3D_qtzHtiG6A5UqaBb8gqeoxgEd1qocTFAgP14XUkLm2d89ricFcs4tKeL6rdpIvaT109zh5PoLS581yKcz6Z-2FbyypWNizaIkWN2fGeRY19SpB7Hq9oi9eDc-2B0gTsA7O4fDLM9vULGrE0Alux5sUuMTUUmrJVSnGP8Ls0fB-2FDRC6VSKOOlWkBuxys59QIJzODbi12lHE7Yg9c08tzIKaRcqMwem7VcFREst02cnBWm0SYxY0DbtDzgVxo-2FcCf4NUsqJzqwQuv1Iy4xnyEe00yjeRA-3D-3D,

and the page it returned says "invalid code. check your email or try again." See attached screenshot. So basically the user can't create their account....

I'm on a Mac, and I've tried Firefox and Chrome and Safari browsers.