Error response received for the request - status code 500

Dear Team,

Receiving below errror on calling OCR API:

2021-02-01 12:24:50,026 INFO Adobe.DocumentServices.PDFTools.pdfops.OCROperation - Performing OCR on an input file
2021-02-01 12:24:55,325 ERROR Adobe.DocumentServices.PDFTools.core.http.HttpClient - Error response received for the request (status code=500, error message=, requestId=1WvcLFXf3bnZXXQq4XQGxS4PKYPemyBz)

API creds and Private Key have been updated correctly.

Kindly assist with this issue
2021-02-01 12:24:55,338 ERROR OcrPDF.Program - Exception encountered while executing operation
ServiceApiException [message =Error response received for the request: , requestId = 1WvcLFXf3bnZXXQq4XQGxS4PKYPemyBz, httpStatusCode = 500]