GroupDocs.Annotation Cloud embedded Annotation App Not Working

The annotation is not working on our website clients.imglicensing.com/
We get Annotation quota exceeded error when trying to display the file in viewer or annotation tool.
The issue is when trying to call method GetAnnotationCollaborators of GroupdocsService class.
I had raise the ticket as well before Groupdocs Upgrade - Free Support Forum - groupdocs.com

If required can provide the user id and private key to verify the subscription.
If the tool needs to be upgraded to latest version, please also provide the license file.
I am open for a call if required.

@rguptanetsol

We are truly sorry for your inconvenience. We have investigated the issue and found that your subscription was recently downgraded to Free pricing plan due to non payment. And the limit for Free pricing plan is only 100 tokens (chargeable operations), so you faced the Annotation quota exceeded error.

However, we have again tried with your updated credit card and payment is successful now. Please try now your issue should be resolved.