E_ADEPT_NO_TOKEN

I bought an ebook in pdf format with DRM protection and when trying to open the .acsm file I get the following error:

Can not be downloaded
Failed to get the license. Communication problem with the license server:
E_ADEPT_NO_TOKEN

Is the problem mine for doing a wrong procedure or should I file a claim with the provider who sold me the book?

Any help is welcome!