Files are not backing up

Ive had my WD essentials for a couple of years and back up my documents and photos monthly. I have just discovered  that nothing has been backing up for a long time . It says my Back up has been successful each time so Ive never checked the contents/fies /photos on the WD until today. Can anyone suggest what to do? I am not very technical so would appreciate  what to do in a simple way. Thanks

How do you backup your data, I meant do you use a software if so, what’s the name of the software. Can your povide the drive model number?

Thanks for your reply.

I am sorry but as previously mentioned I am not very technically literate especially with computers  so I wil try my best to explain what I have done.

I have a WD Passport Essential 500 external hard drive which I purchased 3 years ago.

At the time I installed it and copied all my files from my computer onto it.

I checked and found that at the time that this did occur.

I arranged on my computer  (Control Panel- Back up and Restore Files) to backup my files from my computer monthly onto the portable hard drive.

Each month I receive the message that this occurred and unfortunately I did not check on My Passport  that all the files had infact updated.

I only checked it this month and to my horror I have found that the files have never updated since I first installed My Passport.

Since my discovery I have copied and pasted my thousands of photos from my computer to My Passport so at least I have them now saved.

I cannot see if there is any software with my model eg WD Smartware. It was suggested that I uninstall any software and reinstall the latest version but I am not having any luck.

Any hints would be much appreiated. Thanks