Regarding kindergarten cost reduction

Hello and thank you for your work! I have the following problem, I came in Germany in the autumn with my family, husband and daughter, since I started a master. I found a kindergarten and my daughter started there, I was inform that I can have a reduction of the kindergarten cost so I applied in the municipality and was granted the reduction. I have a mini job and will start another one soon, my husband is not working yet. When I moved in a specific city, while I was living in a different rural location of the same discrict, I reapplied in the city municipality this time for the reduction and I was told that they can not take into account my application and can not give me a reduction because my income is extremely low. Is this even possible? Only with a higher income and if my husband gets social assistance they told me that they may grant me the reduction. So a family with a very low income can not be helped with the kindergarten cost but if a family earns more money they can, is this thing reasonable and lawful?