Cannot read pdf file digital editions

Hi

I am getting this error when I try open a pdf on digital editions.

error getting license server communication problem

e_lic_already_fulfilled_by_another_user

I bought the book a while ago at my previous company, and I think I used my company email to authorize it.

It has been a while since then and I don't know what the email address is.

I have got my proof of purchase from the online company where I bought the book from.

Please can someone assist me.

Spider.