! Undefined control sequence. \tightlist

I am getting the following error when building a rticle document with markdown.

rmarkdown::render("Prolfqua.Rmd", output_format = acs_article())

and this produces the following error

! Undefined control sequence.
l.400 \tightlist

Error: LaTeX failed to compile Prolfqua.tex. See https://yihui.org/tinytex/r/#debugging for debugging tips. See Prolfqua.log for more info.

However, I know that this was working some time ago. I suspect that this error might be related to updating to R.4.1 and reinstalled all packages. Any suggestions?

Bdw I am on windows and I am using MiKTeX 2.9 .

The pandoc version in my path is:
C:\Users\wewol>pandoc --version
Compiled with pandoc-types 1.20, texmath, skylighting
Default user data directory: C:\Users\wewol\AppData\Roaming\pandoc
Copyright (C) 2006-2020 John MacFarlane
Web: https://pandoc.org
This is free software; see the source for copying conditions.
There is no warranty, not even for merchantability or fitness
for a particular purpose.

Also checked this thread:

However, since I am using rticle and all was working before, I would not even know where "your custom template" is.