Package check result: ERROR

Check: re-building of vignette outputs, Result: ERROR
  Error(s) in re-building vignettes:
    ...
  --- re-building ‘gaawr2.Rmd’ using rmarkdown
  Error: processing vignette 'gaawr2.Rmd' failed with diagnostics:
  there is no package called ‘bookdown’
  --- failed re-building ‘gaawr2.Rmd’
  
  --- re-building ‘web.Rmd’ using rmarkdown
  Error: processing vignette 'web.Rmd' failed with diagnostics:
  there is no package called ‘bookdown’
  --- failed re-building ‘web.Rmd’
  
  SUMMARY: processing the following files failed:
    ‘gaawr2.Rmd’ ‘web.Rmd’
  
  Error: Vignette re-building failed.
  Execution halted