Hi @b2sargent; thanks for posting on our Community.
I'm assuming that you're referring to our self-served look up tool; correct?
While we're at it, can you clarify if the email you mentioned comes from us or your payment vendor directly?
Your transaction ID is the 12-digit alphanumeric code located on the Dropbox line item on your bank or credit card statement so you may want to reach out to your bank for the precise transaction ID.
In any case, please keep me posted.