When you refresh a sandbox, SSO settings are usually incorrect. After a refresh, you usually have to log in and fix those settings, and possibly fix the settings in Identity Connect as well. Fortunately, all is not lost. You can usually log in by appending ?login to your login URL. For example: https://mydomain.cs20.my.salesforce.com?login should allow you to log in, assuming that's your correct login URL. If that fails, you can contact support, and they can fix your Salesforce settings for you by disabling forced SSO logins.
When you refresh a sandbox, SSO settings are usually incorrect. After a refresh, you usually have to log in and fix those settings, and possibly fix the settings in Identity Connect as well. Fortunately, all is not lost. You can usually log in by appending ?login to your login URL. For example: https://mydomain.cs20.my.salesforce.com?login should allow you to log in, assuming that's your correct login URL. If that fails, you can contact support, and they can fix your Salesforce settings for you by disabling forced SSO logins.
Reference -> https://salesforce.stackexchange.com/questions/107258/cannot-login-into-sandbox-after-refresh
Hope this helps !
Thank you.
You can contact your salesforce admin to reset password.