Look very carefully at the hole in the centre of the disc and see whether it's cracked, because that is usually the cause of the symptoms you're describing.
Basically, if you're not very careful taking discs out of their cases, or putting them back in, then you can crack the inside of the disc where it sits on the spindle of the DVD drive.
Even the tiniest crack will cause the disc not to be read by the drive, since the hole will be slightly too big for the spindle to grip properly and the disc will slip when the spindle tries to spin it, creating the disc read error.
If this is the case and your discs are cracked, then there's nothing you can do to fix it and you'd shouldn't even try to use the disc as it could shatter inside your console.
To prevent this from happening to any of your other discs, just keep them in a CD wallet rather than put them back in their cases, as it's the hard plastic spindles inside the cases which can crack the discs unless you fully depress them each and every time you take a disc out and put it back.
I've been keeping all of my game discs in a CD wallet for years for this reason and this reason alone.