Shiny app produces errors instead of plots after deployed in

This is my app it works fine but after deployed it produces errors. How can I find what is going on? Can you see my logs?If not I can send them to you.

We don't have enough information to help you out, Could you check what your app's logs say?

They are so many. I downloaded them would you like me to send it to you?

You should probably read the most recent one only. Look for the word error

Error in gsub: input string 1 is invalid UTF-8

are there many places in your code where you use gsub ?
can you recognise the point of failure as it relates to your code ?