Changing domain of APP

We are moving our site from one domain name to another (on the same server), and we have an SSL for both, we have managed to access the app via the new domain, but we are getting this error." Error%20%5BERR_TLS_CERT_ALTNAME_INVALID" - so looks like an SSL error, how do we tell Auth0 to accept this SSL cert?

I Managed to figure this one out for myself, it was a setting in IIS - so not related to Auth0.