I'm doing clustering using k-maps but in the end all the vales come in the same cluster

Question

This is the data im working with

Using cases 6,9,15 as the initial cluster centers

Second Using the mean values of the clusters insted of the initial values. There some change in the clustering.

ThirdI repeated the same steps but I dont think this should be the table. I'm using the formula SUMXMY2 in the excel cell for sum of squared differences.