I receive the error saying: "Your message below hasn't been delivered due to an error"

This issue is rather rare but you might have seen the following notification:

There are several things you can do when facing such an issue:

1. Try to re-send the same ticket in a while;

2. Use the Instagram app itself and send a response from there.

This issue is of a temporary nature. If the problem persists for quite a long time, please contact us.