Error while running an app on shiny-server related to port

I am trying to run an R Shiny app (called “calculator”) from Ubuntu 22.04v. The R version is 4.3.2. I am trying to create a home server to run this app. However, when I try to run the url, I receive an error “port not found“. My app resides in
/srv/shiny-server/calculator. When I am running the app through RStudio, its running perfectly fine. The sample-apps to test shiny-server is also running fine.

calculator/
├── app.R
├── deployment_to_polished_script.R
├── deps.yaml
├── global.R
├── google-analytics_2730uwjerlu32.html
├── google-analytics.html
├── helpfiles
├── logs
├── R
├── report.Rmd
├── server
├── src
├── transl_json
├── ui
└── www

Part of the error log for running “calculator”

The following object is masked from 'package:plotly':

add_image

df_standardSolutions
db_fert
element_data
Warning in data.frame(..., check.names = FALSE) :
row names were found from a short variable and have been discarded
Warning in data.frame(..., check.names = FALSE) :
row names were found from a short variable and have been discarded
Error: object 'port' not found
Execution halted

I was trying to load the app from Desktop by changing the path in the /etc/shiny-server/shiny-server.conf

site_dir /home/ubiota/Desktop/calculator

However, this gave a permission error. I am out of ideas now. Please help !