You can disable comments under your Instagram post directly from your feed. This means that no (new) comments can be created under the corresponding post.

There are two ways to disable comments under an Instagram post. If there are already comments under the relevant post, select one of those comments. The context opens on the right. There you can disable comments via the three-dot menu.
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If you want to restrict the comment function right away, open your filter and select Instagram Media in the post types and select the respective profile. You also need to change the view from Unresolved to All items. There you will find your own published posts and can also deactivate the comments via the three-dot menu.