Download charts in flexdashboard

I am trying to use a download button in the input column of a flexdashboard to download a collection of charts rendered as *.pdf. The entire dashboard works just fine, and the download button renders properly; however, when I click the download button, the file that does get downloaded does not contain the intended charts. The warning I get from my Mac when it tries to open the file is that the file might be damaged or that it's a form that Preview (or Acrobat) doesn't recognize. The following is a highly redacted form of my code that contains the problematic sections. Any guidance on how to get charts to download in a flexdashboard as charts download in Shiny?

Thanks in advance,
RB

---
title: "My Model"
runtime: shiny
output: 
  flexdashboard::flex_dashboard:
    theme: cerulean
    vertical_layout: scroll
    orientation: rows
---

```{r global, include=FALSE}
library(shiny)
library(shinyBS)
library(shinyWidgets)
library(flexdashboard)
library(tidyverse)
library(readxl)
library(knitr)
```

```{r Inputs}
downloadButton("downlaodReport","Price Comparision Report")

downloadHandler(filename = function() {
     filename = paste0("Analysis-", Sys.Date(), ".pdf")
   },
     content = function(file) {
       pdf(file, width = 8.5, height = 6.14)
       renderPrint({ output$gg.prob.win.price() })
       dev.off()
   }
)
```

```{r priceProbWinChart}
renderPlot({
gg.prob.win.price <- {## ggplot code goes here ##}

plot(gg.prob.win.price)
})
```