Error in deploying application to Shiny: "Error in value[[3L]](cond): there is no package called 'leaflet'

Hello everyone, I am having an issue regarding deployment of a Shiny app. The shiny app.R file works completely fine on my local machine, but when I go to deploy it to my account, I keep getting this error:

Error in value[[3L]](cond) : there is no package called 'leaflet'
Calls: local ... trycatch -> tryCatchList -> tryCatchOne -> <Anonymous>
Execution halted

This is really strange to me because I have leaflet as one of the libraries used in my Shiny App


Is there something that I am doing wrong or did not include?

Thank you very much in advance.