i am trying to render a rmarkdown document into PDF and i am getting an error message :

! Use of @startpbox doesn't match its definition.
<inserted text> @startpbox {
                             @{}ccc@{}}
l.241 begin{longtable}[]{@{}ccc@{}}

what is this ?

below it says :

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

the .log file says the same message.I have visited the site from yihui that suggests and i have updated the library.I do not have restrictions from group policy.So what is it ?