Confusion about not being able to breed

So I've been trying to figure out how to breed again with my breeding male (this is after I've already done the breeding quest) but for some reason I don't seem to be able to. When I go to the breeding page and click on the drop down menu for females it only shows "Unsorted Wolves." But since all my wolves are in a cave together no wolves show up and I can't pick a female to breed with him.

Can breeding males only breed with unsorted wolves? Did I accidentally mess up by putting my all wolves in a cave together and if so is there a way to take a wolf out of a cave so that they would then be able to breed? Or is there some other reason that this doesn't seem to be working?

It appears that none of your females are in heat at the moment, a little flame icon should appear on your den page to indicate any females that are ready to breed! Hope this helps!

They need to be in heat, you can see how long until they’re next heat cycle on their page.

The female needs to be in heat to be able to breed with him, which you can check when their next heat is in breeding info tab in ur female wolf's description. Once you have one in heat id assume it would pop up in that list instead of "Unsorted Wolves" cause in most games they just show the unsorted spot when you have nothing you can choose