Perovskite reaction equation (KMnF3)
Quoting from Weller, M.; Overton, T.; Rourke, J.; Armstrong, F. Inorganic Chemistry, 6th ed:-


  $\ce{KMnF3}$ is prepared by the addition of $\ce{KF}$ to $\ce{Mn^2+}$ solution. [...] Fluorination of $\ce{MnF2}$ in presence of an alkali metal fluoride leads to the complex Mn(IV) fluorides of composition $\ce{M2MnF6 (M = K, Rb, Cs) }$.


So, the reaction is all right.