Certified GKH Gardening Expert
This is probably a sign of too much water. It is still early, so it hasn't caused any real damage yet. You should only water after the top 3 inches or so of soil is completely dry, or even further as they are quite drought resistant. This will prevent any issues.
For now, here is an article on their care: https://www.gardeningknowhow.com/houseplants/kalanchoe/growing-mother-of-thousands.htm