Bad hatch rate GQF 1502 help

[BigHead]

I’m getting about 50-60% percent hatch rate. I always have ones that come spay legged and crooked toes. Humidity been 45-55 first 18 days and last 3 days 60-70ish. Any recommendations

 

[BirdsBeesTrees]

How many roosters do you have per how many hens? Some hens might not be getting bred?
Splay legs and crooked toes means you temperatures got too hot during a critical time in incubation. Some places in your incubator may be hotter. Do you have any additional accurate/calibrated thermometers inside?
What protein percentage are your hens getting? I do 20% protein.
I incubate around 30-40 max humidity.