valuebox missing true/false statement - if-statement

Question

I am attempting to have two if else statements in a renderValuebox in shiny R. Here's the code:
observe({
a <- which(blkname==input$e0)
start <- input$dateRange[1]
end <- input$dateRange[2]
confInt <- input$CI
inc <- input$increment
output$Name <- renderText(paste0("Overview of ",input$e0," block"))
start1 <- as.character(format(input$dateRange[1], format="%B %d %Y"))
end1 <- as.character(format(input$dateRange[2], format="%B %d %Y"))
output$Head <- renderText(paste0("Distribution of dry matter across ", input$e0, " between ",start1, " and ", end1))
pts$DryMatter <- pts$DryMatter+(pts$Amend*inc)
pts$DryMatter <- round(pts$DryMatter, digits=2)
grap <- pts[which(pts$Date>start&pts$Date<end),]
grap <- grap[which(grap$paddock==a),]
grap$DryMatter<- round(grap$DryMatter, digits=2)
yup <- round(mean(grap$DryMatter), digits=2)
nump <- nrow(grap)
grapdevdm <- grap[which(grap$Amend==min(grap$Amend)),]
grapdev <- sd(grapdevdm$DryMatter)
grapsampnum <- nrow(grapdevdm)
grapdevmean <- mean(grapdevdm$DryMatter)
cv <- (grapdev/grapdevmean)*100
sampReq <-(1.7*1.7)*(cv*cv)/((100-confInt)^2)
~
output$treenum <- renderValueBox({
valueBox(
paste0(nrow(grap), "Trees sampled out of ", sampReq, "required."),
if(nrow(grap)>=sampReq){
icon = icon("thumbs-up", lib = "glyphicon")}else
{icon = icon("thumbs-down", lib = "glyphicon")},
if(nrow(grap)>=sampReq){ color = "green"} else {colour = "red"}
)
})
I am receiving Warning: Error in if: missing value where TRUE/FALSE needed
However both if else is completed, maybe I am missing something.
Cheers,