Honda hrm215 cutting issues

[Lebmet5]

I have a honda harmony hrm 215 mzbb-6054758 sxa I think is from 1994. It runs great but as soon as the grass gets a little high the blades want to stall out, wondering what would be the cause ?

 

[BlazNT]

Adjust the cable for blade engage and or replace the belt.
Manual
cdn.powerequipment.honda.com/pe/pdf/manuals/31VEZA10.pdf