Almost lost my first magnet today when it unattached from the hook. How do i prevent that in the future?

I just bought my first magnet from brute magnetics. I went out for the first time with it in a rural creek. About an hour in as I was pulling in the magnet, it somehow unattached itself from the hook and was left at the bottom of a muddy creek about a foot deep. I went in after it and ended up finding it, but now I’m afraid that it will happen again in a spot where I can’t wade in shallow water to find it. Has this happened to anyone else, and how do you prevent it to the best of your ability?

This is what I bought: https://brutemagnetics.com/collections/magnet-fishing/products/350-lbs-pulling-force-round-neodymium-magnet-fishing-bundle-includes-100-ft-550-paracord-and-threadlocker