E_LIC_ALREADY_FULFILLED_BY_ANOTHER_USER error after getting work done on PC

My problem is this: I purchased a standard back in June 2019.  This required Adobe Digital Editions to read the standard.  I have recently had work done to my PC, and I now cannot access the standard due to the error E_LIC_ALREADY_FULFILLED_BY_ANOTHER_USER.  The organisation I purchased the standard from are not answering emails or phone calls.  My question is: how can I get access to this standard again?