I have used my little corn shapes for cornbread three times; the first batch I had to soak my little skillet for a day

the second batch perfect they just fell out

The third batch I had to scrubb with a toothbrush

Does anyone have any suggestions on the best way to clean the little skillet in case of sticking

I seasoned it myself with bacon grease and then baked and used crisco to coat the skillet all three times. Not sure what is causing the inconsistancy?
Thank you in advance!