Uneven Cut

[Supper Grassy]

I added air to my tires (not sure what they should be up to) and then cut and once i finished cutting i saw that the cut was uneven..
How can i get my cut back being level?

Machine:
Snapper 36"
Model PP7125KV


also what blades do you recommend?

[k911lowe]

put a level on the deck to see.you might have to adjust.