Looks like you opened your .manager database file with a later version of manager, which has the effect of updating the schema version embedded in your file.
It is possible to rollback this embedded schema version, so that the file can be opened with your older manager software.
You’ll need to have sqlite installed. See How To Download & Install SQLite Tools
You’ll also need to find an old backup .manager file, from which you can extract the schema version of the Manager software that created the file. See Database versioning - #3 by d3mad
The rolback process makes a change to your database file, so please make a copy before you do it. There may also be changes that the newer version of Manager made, so if you succeed, have a good poke around your data before you celebrate.
For the process, see Almost Everyday there are new versions - #15 by Bob_Hunt (make sure that single quote marks are used; not backticks).
I guess from now on that you’ll be doing daily backups. 