I found if I tried to max out deadlift week in week out I didn't increase or even couldn't lift what could before

so lowered weight and done more reps or done 5x5 traning or my fave at moment pyramid up and down eddie hall style

and found an increase when finally went for the max lifts no more than once month
personally hit pb with 190kg yesterday but was just the one rep and didn't look the neatest lift but got it up