Issue 

•⁠  ⁠Salesforce users cannot use the same username and password simultaneously. 

Solution 

•⁠  ⁠You can create multiple passkeys for different users while using the same credentials. 

•⁠  ⁠Log in to the Sandbox. 

•⁠  ⁠Go to User Settings. 

•⁠  ⁠Click Advanced User Details. 

•⁠  ⁠Find the Passkeys section. 

•⁠  ⁠Click Add Passkey. 

•⁠  ⁠Share the generated passkey URL with the users who need access to the Sandbox. 

Note 

•⁠  ⁠Users should first log in to the Sandbox using the shared username and password. 

•⁠  ⁠When the system prompts for a passkey, they should paste the shared passkey URL to complete the login.