Frozen milk took more than 24hours to thaw in "frige", is it still safe?

Yes. milk is good for 24 hours after it is thawed. Keep this in mind....the 555 rule. milk is good for 5 hours at room temp....5 days in the fridge.....5 months in the freezer. And once frozen milk is thawed it is good for 24 hours, so don't worry. I follow these guidelines and my son is thriving.