Google Play error -24???

[AC Question]

I have smartphone Android Jelly Bean. My phone has been TOTALLY messed up recently due the "Time Service" and "MonkeyTest"--super annoying! - And just yesterday "Android System" had been popping up on my screen NON-STOP! (I think my phone's gonna die soon~ :/)
Well anyway, I have reset my phone (of course I have backed up my apps.) When I tried to restore them, some have been restored and some couldn't be installed, and I don't know why. I tried downloading them from Google play but it can't!!! And it keeps on saying " Can't intall App --- (error code -24)

Could someone please help me with this ?
Please don't say my phone's at its END!! :'(
Any Help would be very much appreciated! Thank You

 

[B. Diddy]

Welcome to Android Central! Does this happen on both wi-fi and mobile data?

Try going to Settings>Apps>All, select Google Play Store, and Clear Cache/Clear Data, then Force Stop. Do the same for Download Manager. Now try again.

If that doesn't work, try going to Settings>Accounts-Google, select your Google account, and remove it completely from the phone. Then add it back again, and see if that helps.