Remedy this ASAP! Meaning unless you have actually tried and successfully restored all needed data, you have no idea if your backup is worth anything at all. Worse yet, you may have a false sense of security, thinking your backup will be there if you need it. Also make certain you have multiple backups (a series, I use monthly, quarterly, and annual sets).
Restore into a temporary folder, not over your live data, then compare. Better yet, restore onto your spare computer and see if the results are satisfactory. 4 times a year is reasonable to test your backup, I use the quarter changes. Ideally, your test involved starting with nothing at all, meaning install the needed software, see if you have the logins/passwords/etc., see if you can restore, and what is restored. Yes, it takes effort, but if done, you will be absolutely certain you can start over at any time, with no existing machine needed.