Failed to load resource: the server responded with a status of 500 (Internal Server Error) in a flask application hosted on IIS, running fine localy

Question

My web.config file code-

<?xml version="1.0" encoding="UTF-8"?>
<configuration>
    <system.web>
        <identity impersonate="false" />
        <customErrors mode="Off"/>
        <compilation debug="true"/>
    </system.web>
</configuration>

I have hosted the flask application on IIS Server locally it is running fine but when it is hosted it is producing this error with 500 code.

It was showing error here on console in browser when i clicked on the error on that fetch -

const response = await fetch('/app', {
                method: 'POST',
                headers: {
                    'Content-Type': 'application/json'
                },
                body: JSON.stringify({
                    systemName: systemName,
                    AID: AID,
                    Ticket_no: Ticket_no
                })
            });

So my question is that how it can be solved is it requires more permissions or there is some other way to solve this