That’s not what the screen shot is saying.
If you can’t open the file with AxCrypt because it says the password is wrong, well, it is.
A likely scenario is:
1) You upgrade to AxCrypt 2.
2) You sign up, set your password and sign in (thus typing your password at least three times) (on May 25).
3) You open the file in question, and get a new prompt for a “file password”.
4) You enter the right original AxCrypt 1-password.
5) The file opens, and is automatically converted to AxCrypt 2, and using the new AxCrypt 2-password.
6) Time passes. 3 Days to be more precise.
7) You start AxCrypt and realize you have forgotten the password you set in step 2. (On May 28).
8) You issue a password reset. (this will allow you to sign in again, not to open files encrypted with the old password).
9) You sign in to AxCrypt 2 again, but can’t open the file.
10) You uninstall AxCrypt 2, and re-install your old AxCrypt 1 version.
11) You get the message in the screen shot.
You need to remember the password you set on May 25.