okay so i have my ball python collection, i have been trying to breed 4 of of my females that are all over 2,000grams. i have been putting my males with them for the last two years and nothing, i dont get eggs, i dont get anything. what am i doing wrong?

i have them in a rack from animal plastics and i have the temps set at 90 during the day and 86 at night.

can someone please help me out, my dad is freaking out because we have spent well over 20k on all the snakes i have and i havent been able to get 1 clutch out of them.

the females im trying to breed now are

0.1 normal over 4,000g to a desert male thats about 600-700g
0.1 normal a little over 3,000g to the same desert male
0.1 piebald 3,000g to a male piebald about 1000 grams
0.1 woma about 2,000 grams to the same desert male above.

since i am using the desert for many projects i do give him breaks when switching tubs. 3 days on and 6 days off and then he goes to a different female.

please help me out, ive had these snakes for over 5 years and im freaking out because i havent gotten any eggs.