I can see the responses in the table, just not connected to the original post.
Looking at the replies in wp_posts, it appears that the post_parent has been set to zero and associated postmeta (_bbp_topic_id) has been set to null.
The question is how could this have happened?
hmm – what other bbpress related plugins do you have?
A boatload unfortunately.
Admin Columns
Adminimize
Advanced Classifieds and Directory Pro
Advanced Custom Fields
Advanced Custom Fields PRO
All-in-One WP Migration
All-in-One WP Migration Unlimited Extension
amr shortcode any widget
bbP shortcodes
bbPress
bbPress Style
bbpress wp4 fix
bbpress wp4 fix2
Better Search Replace
Bulk Delete
Check Email
Classic Editor
Code Snippets
Contact Form 7
Envato Market
Events Manager
Events Manager Pro
GA Google Analytics
Goodlayers Core
Goodlayers Personnel Post Type
Goodlayers Portfolio Post Type
Goodlayers Twitter
Google XML Sitemaps
Horizontal scrolling announcements
If Menu – Visibility control for menu items
Image Upload for BBPress
Image Upload for bbPress Pro
Intuitive Custom Post Order
Login or Logout Menu Item
Magic Liquidizer Responsive Table
Maintenance
ManageWP – Worker
Media Cleaner
Media Deduper
MemberPress Developer Tools
MemberPress Importer
MemberPress Plus
PAS Vehicle
PDF Embedder
Plugin
Pricing Table by Supsystic
Really Simple CSV Importer
Redux Framework
Reveal IDs
Search & Replace
Simple File List
Simple Lightbox
Slider Revolution
Snazzy Maps
Toolset Types
Toolset Views
UpdraftPlus – Backup/Restore
User Role Editor
User Switching
WordPress Importer
WP All Export Pro
WP All Import – ACF Add-On
WP All Import Pro
WP Engine Automated Migration
WP Google Map Plugin
WP phpMyAdmin
WP-Optimize – Clean, Compress, Cache
WPForms
WPForms Custom Captcha
WPForms PayPal Standard
WPForms Stripe
ok, how many are disconnected, how often is this happening?