Well you can just take it to any clothes alterations place, and they can stitch it up fairly easily. Something like this would take about 5 to 10 minutes of time for them to do. Make sure to tell them it has to be a very strong stitch.
They might even recommend replacing the loops instead of stitching the existing ones. And they can suggest a material that will hold up better, maybe a thick nylon material.
Speaking of nylon, if they're made of nylon fibers, you can try melting them together with a lighter or some kind of flame.
I don't recommend gluing with any kind of glue. The bond probably won't hold up over time. And if it doesn't work, you now have to deal with the glue somehow.
One alternative to stitching would be to use metal rivets. You can get them on Amazon. You might not even need any tools, just a hammer. But keep in mind adding rivets means you lose about a centimeter or two along the perimeter of the loop, because you have to overlap the two ends to make the rivet. That might make the loop too small.
Here's a web site describing how to do it:
But my recommendation is to just go with a clothes alterations place instead. It's fairly cheap, and they know what they're doing.
Hope that helps.