Mag Drives run a little hot, that heats create carbonate precipitation (Scale) which can lock the impeller.
Remove the pump cover and let the pump soaking in vinager over night to dissolve the scale. Pull the impeller out and inspect it for breakage, if it is OK just insure it is clean, Use the vinegar and a round small bottle brush to also clean inside the rotor housing.
Rine the marts in tap water and reasemble.
This cleaning is recommended a minimum of every six months with every three months being optimal.
If it has not locked the cleaning will be ase easy as running the pump submerged in 50% vinegar 50% water solution.