Getting "Internal error - 9603" for manageVPPLicensesByAdamIdSrv API when assigning license for a particular app

Problem Description:

We are using manageVPPLicensesByAdamIdSrv API for assigning licenses for serial numbers. We get "Internal error - 9603" response for this API when assigning the API for valid adamID of an app. When using the same API other apps, this issue doesn't occur. AdamID: 720111835. The license is assigning properly for the same app in VPP License Management 2.0.0 + - Associate Assets API. Currently, we will not able to the new API. We overcame this issue by creating a new location token in the same organization and purchasing the same app in it and using it to assign the license to device for the same app which is successful.

Kindly help us with this issue.

Request:

{"pricingParam":"STDQ","disassociateSerialNumbers":["SAMPLESERIAL"],"adamIdStr":"720111835","sToken":"********************","notifyDisassociation":false}

Response:

{"errorMessage":"Internal error.","errorNumber":9603,"status":-1}