Use ggplot and lmerTest in R running with Ubuntu

Question

for my Statistical analyses, I need to use the Packages ggplot2 and lmerTest.

While installing lmerTest I updated R and was able to use the function. But after this update, I was not able to use ggplot2 anymore. So I downgraded it. If I want to install lmerTest now it shows the Error:

install.packages("lmerTest")

  Warning in install.packages :
  installation of package ‘lmerTest’ had non-zero exit status

   ---- there is no package called ‘lmerTest’ 

When I Google that problem I just find the answer to update R, but then ggplot2 won't work. I cant use lme4 instead because here is missing the p-value.

Is there no way to use both, ggplot2 and lmerTest, with Ubuntu??

I'm definitely no expert. Thanks for any help, sincerely

Maria