My God! You're not having much luck at all with this, mate.
That happened to me once. The playing surface of the disc looked like a skating rink, but somehow it was still readable.
This problem is caused by using cheap cases and not pushing the discs fully home, so that the retaining lugs fail to latch properly.
There is a simple method of preventing the discs from rattling about inside the case and getting damaged when they become disengaged, and that is to pack the empty space between the discs, or between the disc and case when there is only one, with a small piece of bubble wrap.
This will add very little weight to the package and is a foolproof way of preventing damage to the disc(s) in transit, and yet I have never seen it done!