DT::renderDataTable working in viewer pane but not once I deploy the app through shinyapps.io

I created a Shiny app to draw plots from .csv files.
The app is pretty basic where people can upload their .csv files (from a specific template) and the data file will be modified to create several graphs.
Recently someone asked me to have the calculations generated in a table format so I wanted to add that to the app. I managed to have everything working through and I can see the table with the respective calculations in the viewer pane when testing the app but once I deploy the app through shinyapps.io, the table does not show up and instead I have the following message:

Error: An error has occurred. Check your logs or contact the app author for clarification.

When I check the logs I only have this:

2021-07-30T15:00:26.212649+00:00 shinyapps[4181864]:   115: exprFunc [/srv/connect/apps/PK_Modelling/app.R#92]
2021-07-30T15:00:26.212650+00:00 shinyapps[4181864]:   114: widgetFunc    
2021-07-30T15:00:26.212652+00:00 shinyapps[4181864]:   112: func    
2021-07-30T15:00:26.212651+00:00 shinyapps[4181864]:   113: htmlwidgets::shinyRenderWidget    
2021-07-30T15:00:26.212653+00:00 shinyapps[4181864]:    99: renderFunc    
2021-07-30T15:00:26.212665+00:00 shinyapps[4181864]:    13: runApp    
2021-07-30T15:00:26.212653+00:00 shinyapps[4181864]:    98: renderFunc    
2021-07-30T15:00:26.212667+00:00 shinyapps[4181864]:     6: eval    
2021-07-30T15:00:26.212667+00:00 shinyapps[4181864]:     7: connect$retry    
2021-07-30T15:00:26.212663+00:00 shinyapps[4181864]:    94: renderFunc    
2021-07-30T15:00:26.212664+00:00 shinyapps[4181864]:    93: output$table    
2021-07-30T15:00:26.212666+00:00 shinyapps[4181864]:    12: fn    
2021-07-30T15:00:26.212667+00:00 shinyapps[4181864]:     5: eval  

So I actually don’t know what is wrong.

Here is the code for the shiny app with some parts I need to remove for confidentiality reasons:

library(shiny)
library(DT)
library(ggplot2)
library(gridExtra)
library(ggpubr)
library(MASS)
library(RColorBrewer)
library(ggforce)
library(tibble)
library(tidyr)
library(scales)

# Define UI for application that draws a histogram
ui <- fluidPage(

    # Application title
    titlePanel(p("Analysis of data", style = "color:#3474A7")),

    # Sidebar with a slider input for number of bins 
    sidebarLayout(
            
            sidebarPanel(width = 3,
                
                helpText("Please note that CSV file should contain 7 columns named: <STDNR>, <STD>, <ROUTE>, <DOSE>, <TIME>, <PLASMA> and <BLOOD>"),
                         
                fileInput("file1", "Choose CSV File",
                          accept = c(
                              "text/csv",
                              "text/comma-separated-values,text/plain",
                              ".csv")
                ),

                textInput("CPD", label = "Compound Name"),
                
                sliderInput("HCT", label = "HCT",
                            min = 0, max = 1, value = 0.5),
                
                numericInput("Bmax", label = "Bmax", value = 160),
                
                numericInput("Kd", label = "Kd", value = 1),
                
                numericInput("Kns", label = "Kns", value = 0.35)
 
        ),

        # Show a plot of the generated distribution
        mainPanel( width =9, 
            
            #Output: Tabset w/ plots
            
            tabsetPanel(type = "tabs",
                        tabPanel("PK over time", plotOutput("plot1", width="1200px",height="900px")),
                        tabPanel("Blood to Plasma Ratio", plotOutput("plot4", width="1200", heigh="600")),
                        tabPanel("RBC Binding", plotOutput("plot2", width="1200", heigh="600")),
                        tabPanel("RBC Occupancy", plotOutput("plot3", width="1200", heigh="600")),
                        tabPanel("Table with Calculations", DT::dataTableOutput("table"))
            )
            
        )
    )
)

# Define server logic required to draw a histogram
server <- function(input, output) {

    dt <- reactive({
        req(input$file1)
        read.csv(input$file1$datapath)
        })
    
    output$table <-DT::renderDataTable({
      
      dt=dt()
      dt$RBC <- Calculations
      dt$BP <- Calculations
      dt$OCC <- Calculations
      
      is.num <- sapply(dt, is.numeric)
      dt[is.num] <- lapply(dt[is.num], round, 2)
      
      return(datatable(dt, extensions="Buttons",
                       options = list(dom='lBfrtip',
                                      buttons=c('copy', 'csv', 'excel', 'pdf'))))

    })
     
    output$plot2 <- renderPlot({ 
        plot2
    })
    
    output$plot1 <- renderPlot({ 
        plot1
    })
    
    output$plot4 <- renderPlot({ 
        plot4
    })
    
    output$plot3 <- renderPlot({ 
        plot3
    })
    
    
    
}

# Run the application 
shinyApp(ui = ui, server = server)

Any thoughts on what has gone wrong?
Thank you