Notarization throws general error 1018

Hi

We generate a .dmg file for our standalone mac app which can be downloaded from a website.

I'm trying to notarize it during a week already, but all the time get the same error from altool.

Here is the informations of the steps followed.

I am using xcode 11.3 (and already tried to re-install it - still no luck) and Catalina 10.15.2

Using next command I try to sign dmg file which was successfully signed.

xcrun altool --notarize-app --primary-bundle-id  --username  --password  --file Kreo-1.5.7.dmg --output-format xml --verbose

At output log I see next lines:

[2019-12-15 19:39:56 EET]   INFO: The file, metadata.xml, was skipped because it already exists on the remote server.
[2019-12-15 19:39:56 EET]   INFO: The file, Kreo-1.5.7.dmg, was skipped because it already exists on the remote server.

So it means that files has been successfully uploaded to Apple's servers

But finally I get error from Transporter:

  os-version
  10.15.2
  product-errors
  
  
  code
  1018
  message
  Unable to process upload done request at this time due to a general error (1018)
  userInfo
  
  NSLocalizedDescription
  Unable to process upload done request at this time due to a general error (1018)
  NSLocalizedFailureReason
  Unable to process upload done request at this time due to a general error (1018)
  NSLocalizedRecoverySuggestion
  Unable to process upload done request at this time due to a general error (1018)
  
  
  
  tool-path
  /Applications/Xcode.app/Contents/SharedFrameworks/ContentDeliveryServices.framework/Versions/A/Frameworks/AppStoreService.framework
  tool-version
  4.00.1181

Doese anybody know how to solve this issue and what exactly this 1018 error means? Error description is absolutely not helpful