I have used random orbital sanders for many years. The hook and loop connection to a sanding disc will certainly fail if either or both of the following 2 cases occur.
# Dust is allowed to get between the sanding disc and pad - due to not having discs that match the exact hole cutout of the sanding pad. For example, say you have an 8 hole pad on your sander, but buy discs with 4 holes that align. As dust is pulled into the sander, some will creep back through the 4 holes that aren’t being used. This works its way into the sanding disc. As it does, it disrupts the hook and loop bond. This is compounded greatly when you have a dust bag or trap that is packed full. If you keep this empty and blow out your sander every 30 - 60 minutes of hard use, you’ll find the discs stay attached a lot longer.
# Worn pad on sander. Just using your sander (for those that feel the need to push down hard on the tool) for a few dozen hours will cause the hooks on the pad are flattened and stop bouncing back. As they flatten, the connection to the next sanding disc is weaker and weaker. The operator usually gets mad and pushes harder and harder making this problem even worse. The tool needs minimal pressure to do a good job as long as you have the right grit to match the job.
So any solution will include fixing the sanding disc to sanding pad bond. That requires either a replacement pad or being creative as others have suggested here - like using 1” velcro squares and gluing them to the sanding pad. I am all for extending the life of the original pad for as long as possible but to get optimal life out of your sander, you’ll need to keep the trap clean, blow out the sander and pad before and after you use it, and not push incredibly hard when you sand. Best of luck to you!