Slimes are taking a long time to spawn in slime chunks

I opened a slimes chunk in 1.18 of my world and when going into one of the lower levels (around -40) there were a few slimes in that chunk (double chunk).
I eliminated possible places that can spawn other mobs so that in the region only slimes are born. I set up the beautiful farm, however, the only problem is that no slime is being born in the chunk. I would like to know if this is a common problem with other players or if it is some change in the mob spawn pattern.
Ah, I'm far enough away for the mob to spawn, because I already farmed like this in another world before 1.18.