Post hoc test for Kruskal Wallace nonparametric test

I am trying to run a post hoc test for the comparisons that showed significant differences in my Kruskall Wallace test and I keep getting a variety of errors. I dont think i have my data set up right as i keep getting errors such as 'object not found" or "invalid term in model formula. Here is a sample of the data I am trying to run:

LMWSed: 77 0 3.4 22.7 73.5 79 57 19 16 70

group3: ref ref ref ref low low low low high high high high

The script I used was: > dunnTest(LMWSed ~ group3, data = tpah, medthod = "bh") This returned this error: Error in eval(expr, envir, enclos) : object 'LMWSed' not found

I also tried it with quotes around the LMWSed, and had this error: Error in terms.formula(formula, data = data) : invalid term in model formula

Thanks for any help in advance.

Jenn