Hello everyone! I'm registered at a private clinic Now they refuse to …

Hello everyone! I'm registered at a private clinic Now they refuse to issue me a sick leave certificate because I am self-employed, meaning I pay into the EESP. They haven't heard of such a thing and say that I'm not entitled to it. I called the healthcare department for maternity and childhood, there they confirmed that I'm entitled to maternity payments. But since the clinic is private, they can't influence them and call back Now I think about detaching and attaching myself to the state polyclinic, according to my place of residence, as they told me that they will issue a sick leave certificate without problems. What do you think on my deadline will they take me in the