The Heavy Optics Adapter is a rather simple piece of equipment with little to go wrong. However, we have had a few reports of the Heavy Optics Adapter spinning on the magnetic spigot of your Davros, Sentinel or Ascent. When the lever is open this is perfectly normal, however, when the lever is clamped down the friction applied should heavily resist any side-to-side spinning.
Simply use a 3mm Allen/Hex key to apply slight tension to the ring/lever screw. Make sure to check the fit before you take your kit into the field as it is easy to over-tighten this screw, blocking closure of the locking lever.