Link required login, logged in and link no longer works.

"When you say you logged in with a new Dropbox account, on the same email you have previously registered with, can you let me know more?
Did you use a new account for a specific reason?"

->Yes. I have previously registered using the email address example@example-address.com, which is the address at which I received the invitation.
My password was rejected, and I requested a password reset sent to my email example@example-address.com. I did not receive any email, and registered a new account.
My new account was registered with the same email address, namely example@example-address.com.
To rephrase: I am only referring to one (1) single email address, and I am deliberately obscuring it on this open forum for reasons of privacy and preventing spam.
Everything is registered or otherwise related to that single email address, example@example-address.com.

"Can you try to open the link, while you're already logged in your browser to the Dropbox account the sender used to send you the link to? "

->No. I cannot login to another person's account. Why would you ask me to do that?

"If you have a screenshot of the error message you received, feel free to attach it here, so that we can have a visual. "

->Why? I already copied and pasted the error message in my initial post. There is no more information.

"Keep me posted, and we'll take it from there! "

->No problem, Megan! However, I am not mentally disabled, and I would greatly appreciate being treated as a normally functioning adult going forward.