Error in loadNamespace for sparklyr

I'm trying to do library(sparklyr) and got the following error

Error in loadNamespace(j <- i[[1L]], c(lib.loc, .libPaths()), versionCheck = vI[[j]]) :
namespace ‘jsonlite’ 1.3 is already loaded, but >= 1.4 is required
Error: package or namespace load failed for ‘sparklyr’

What does it mean? what do I need to do for jsonlite? Thank you so much.

try to remove jsonlite and sparklyr, then reinstall both, should work.