You can run the below command from the identity server and check for any errors.

```
dotnet Sitecore.IdentityServer.Host.dll
```

From the current error you shared, it looks the certificate thumbprint is not valid `Config\production\Sitecore.IdentityServer.Host.xml` inside the identity server. 

You can get the certicate thumbprint on your machine by running below command.

```
Get-ChildItem -path Cert:localmachine\My
```

Based on your identity server name you can get the value of certificate thumbprint and update on the above file. Once the changes are done you can restart the identity server.

Hope this helps!!! Let me know in case you have any queries.