Just a note…..there are other reasons that steering will fail but as OldMachinist stated the #1 cause is clutch lining (disc). It is an easy repair, ...however, ……from your description, I would not be surprised that you will find that you have damaged the inner or outer (or both) clutch plates. They are highly polished surfaces and any damage to their surfaces will prematurely wear replacement 'linings' (hours in some cases). As was previously stated, there are some serviceable assemblies available on e-bay at this time. Upon inspection, should you determine that the 'clutch assembly' is in good order, my second choice would be the spindle nut (#17 in exploded view) loosening. A loose spindle nut will allow the shaft to turn so the actuating nuts do not function. That nut requires 225 foot pounds and is a more complicated repair as it requires very specific positioning of the actuating nuts. Investment in a manual would be advised.