Unable to uninstall Ring DNA Managed Package

While uninstalling RingDNA managed package from my production org, i’m getting this error.
******An internal server error has occurredAn error has occurred while processing your request. The salesforce.com support team has been notified of the problem. If you believe you have additional information that may be of help in reproducing or correcting the error, please contact Salesforce Support. Please indicate the URL of the page you were requesting, any error id shown on this page as well as any other related information. We apologize for the inconvenience.
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Error ID: 221160858-35924 (894020651) ******
Could someone please help me on this?
Thanks,