Hi AhmedTaha-3595,
I see that you are using onmicrosoft.com email ID while logging to OPDG.
In one of the prerequisites, it is mentioned that username@keyman .onmicrosoft.com will only work if you have Office 365 offering.
If you signed up for an Office 365 offering and didn't provide your work email address, your address might look like username@keyman .onmicrosoft.com. Your account is stored in an Azure AD tenant. In most cases, the User Principal Name (UPN) for your Azure account is the same as your email address.
Can you please search for Azure Active Directory and confirm whether your tenant is offering is Office 365. Search for "Azure Active Directory" and in the overview of Azure Active Directory you will see Licence details.
I was able to reproduce the issue if the tenant is not an Office 365 offering such as Azure AD Free etc.
Update:
If your tenant offering is Office 365 and still facing the issue then this is a known issue and the product team is working on this. Right now the ETA to deploy the fix is 9/13 and can be changed due to unavoidable situations. Will keep you posted once fixed.
Update 9/14:
The issue is fixed now and working as expected.
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