How to fix missing caption/first comment issue when posting a new post
Have you tried scheduling your post?
Sometimes this issue can occur when your Instagram Bot Follower and Instagram accounts timezones are not set the same. Try scheduling your post a few hours in advance to see if this will resolve the missing caption/first comment issue.
Have you tried using a new proxy address?
With the latest Instagram anti SPAM API changes, your Instagram account may have received a low trust score. In order to get around this and improve your account trust score, you need to use a custom proxy.
More information about how to get a custom proxy can be found here.