My plugin Appointments+ has an error code

I have a weird error code on my page “Request an Estimate”, wondering how to get rid of that… this is the code I used before that I copied and pasted from a friend a while ago:

[su_spoiler title=”Request a Call” style=”fancy” class=”my-custom-spoiler”]

[inbound_forms id=”138″ name=”Request an Estimate”]


[su_spoiler title=”Schedule Your Estimate” style=”fancy” class=”my-custom-spoiler” open=”yes”]

[app_services autorefresh=”1″]

[app_service_providers empty_option=”Select Service Provider” autorefresh=”1″]


[app_monthly_schedule add=”1″]

[app_pagination month=”1″]

[app_confirmation button_text=”Book Appointment!”]