I am waiting on response from Customer support but thought I’d attempt the forum as well. I need help getting back into my account.
You should be able to log in (if you recall your username/password), or reset your password if you don’t, at the link above.
Once logged in you should be taken to a page that shows your owned software, including download links and license keys:
Thank you. My problem is, the email I think I used is no olonger available to me. And the system wants to send me a reset to that email. I also can’t remember the password I used. Got to love old age.
I have sent two requests into DxO. One last night and one just now, asking for help. I have given them my current email address so that they can reach me so we can chat. Another problem is I had to wait until now to get any help because of the weekend and also because they don’t have a chat online. So I need to wait. I’m wanting to upgrade my NIK and not have to pay full price for it, so I’m asking them for help to find my original account and activation information. I don’t know how to find it on my iMac. I’ve requested they change my email to my current one if they can find my old account.
Unfortunately it sounds like it’s in DxO’s hands - and unless you’re paying for their premium support - you’ve got to wait for whenever they get back to you. If you can’t remember or reset your current account, the options become quite limited I think 
@Tdeitr , do you happen to have a backup of some kind or password manager?
They might hold the information you need to access your account.
What version of the Nik Collection are you currently using? If it is not a recent version you may not be entitled to upgrade pricing. I’m not sure what the current policy is although some have suggested it’s n-2. If that is accurate, you would only be able to get upgrade pricing if you currently have the Nik Collection 6 or the Nik Collection 7.
Mark