Got a 2022 zforce800.  Has about 600 miles on it. Water/mud got into the external clutch/belt housing. Cleaned housing out.  Belt looks in good shape.  With engine on, shift from any selection is extremely hard. And clutch tries to disengage right off idle.  Jacked rear end off ground and ran.  With engine on I can shift thru all selections As long as I do not apply brake.  When brake is applied, shifting becomes almost impossible.

What steps should I take to get this fixed?

Thank you all