If you switched to a different server, then presumably you also have a different public IP address. Easy to check e.g. by opening a console / command prompt and try “ping 5c46fa289c89f.streamlock.net” - it’ll show you which public IP address that hostname points to.
And if it’s the public IP of your old server, you need to log in to your Wowza Account, then go to the StreamLock tab under My Account (https://portal.wowza.com/account/streamlock), and in the list of entries, find the entry that has the correct hostname.
In the IP Address column, click the “change” link and set the public IP address of your new Wowza server. Save your changes, then wait at least an hour (or follow Wowza’s instructions for how long you have to wait), because Wowza will generate a new certificate for you. After the wait, re-login to the StreamLock page, download your new certificate and add it to your new server - overwriting (or deleting) the old certificate.
Finally, restart Wowza.