TKS fluid ?
I’m not sure but are you using the type of fluid that is intended for aircraft equipped with TKS anti icing systems ?
What you need is a type 1 deicing fluid kilfrost is one brand that you could try. Don’t use Type 2 de- icing fluid as the thickening agent prevents it coming off the airframe during take off at GA aircraft speeds, type 2 is intended for use on high speed Aircraft.