Error in plm package

Hi all, I am new to R and I face some problems while using summary in plm package. I created some codes like:

pgmm_test <- pgmm(fhpolrigaug ~ lag(fhpolrigaug, 1) + lag(lrgdpch, 1) | lag(fhpolrigaug, 2) + lag(lrgdpch, 2), model = "onestep", index = c("code_numeric", "year_numeric"), data = data[data$sample == 1, ], effect = "twoways")

summary(pgmm_test, robust = TRUE, time.dummies = TRUE)

There is no problem when I run pgmm_test code. But it exists an unexpected error when I am using summary function:
Error in !class_ind : invalid argument type

Therefore, I tried to update my Rstudio's version and reinstall plm package. It worked well the first time after my reinstall but when I reopened my r file, this error appeared again. Is there any solution to my problem? I am sure that my code pgmm_test is not wrong. Thank you so much in advance.

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