Here we go…
[39] pry(main)> PostReplyKey.where(user_id: 36)
=> [#<PostReplyKey:0x0000558954b92d68 id: 9793, user_id: 36, post_id: 3409, reply_key: "00257885-fe73-e76d-09fb-f0f708c2f032", created_at: Sat, 03 Oct 2020 19:37:20 UTC +00:00, updated_at: Sat, 03 Oct 2020 19:37:20 UTC +00:00>,
#<PostReplyKey:0x0000558954bd6e78 id: 9120, user_id: 36, post_id: 3174, reply_key: "b726e441-1c6c-bd60-27ac-8d8d5feef3d7", created_at: Fri, 02 Oct 2020 14:21:48 UTC +00:00, updated_at: Fri, 02 Oct 2020 14:21:48 UTC +00:00>,
#<PostReplyKey:0x0000558954bd6db0 id: 9802, user_id: 36, post_id: 3413, reply_key: "86e179a1-7516-616c-1040-c26c0539f39d", created_at: Sat, 03 Oct 2020 19:41:36 UTC +00:00, updated_at: Sat, 03 Oct 2020 19:41:36 UTC +00:00>,
#<PostReplyKey:0x0000558954bd6ce8 id: 9821, user_id: 36, post_id: 3418, reply_key: "573f48a4-8263-4759-44f0-f6cb26b66f38", created_at: Sat, 03 Oct 2020 20:37:40 UTC +00:00, updated_at: Sat, 03 Oct 2020 20:37:40 UTC +00:00>,
#<PostReplyKey:0x0000558954bd6c20 id: 9822, user_id: 36, post_id: 3419, reply_key: "9371479c-eeb4-1009-176d-761a854a4ddb", created_at: Sat, 03 Oct 2020 20:40:08 UTC +00:00, updated_at: Sat, 03 Oct 2020 20:40:08 UTC +00:00>,
#<PostReplyKey:0x0000558954bd6b58 id: 9400, user_id: 36, post_id: 3245, reply_key: "e1cd57aa-a811-21f9-5e24-84439e184a8e", created_at: Fri, 02 Oct 2020 21:35:12 UTC +00:00, updated_at: Fri, 02 Oct 2020 21:35:12 UTC +00:00>,
#<PostReplyKey:0x0000558954bd6a90 id: 8613, user_id: 36, post_id: 3067, reply_key: "407edb15-e89d-4369-9fee-1e5eab83385d", created_at: Wed, 30 Sep 2020 13:50:17 UTC +00:00, updated_at: Wed, 30 Sep 2020 13:50:17 UTC +00:00>,
#<PostReplyKey:0x0000558954bd69c8 id: 9517, user_id: 36, post_id: 3288, reply_key: "140a48d2-1a40-d429-f6e2-2bbe37b4865d", created_at: Sat, 03 Oct 2020 09:54:40 UTC +00:00, updated_at: Sat, 03 Oct 2020 09:54:40 UTC +00:00>,
#<PostReplyKey:0x0000558954bd6900 id: 9736, user_id: 36, post_id: 3388, reply_key: "76cacf9b-5353-0653-806d-f3c2df6689eb", created_at: Sat, 03 Oct 2020 18:37:11 UTC +00:00, updated_at: Sat, 03 Oct 2020 18:37:11 UTC +00:00>,
#<PostReplyKey:0x0000558954bd6838 id: 8643, user_id: 36, post_id: 3011, reply_key: "6d384213-98db-652c-89eb-1979731bb311", created_at: Wed, 30 Sep 2020 20:55:31 UTC +00:00, updated_at: Wed, 30 Sep 2020 20:55:31 UTC +00:00>,
#<PostReplyKey:0x0000558954bd6770 id: 9772, user_id: 36, post_id: 3400, reply_key: "1e9e0b2e-ecd6-3654-d0da-6e01982a890f", created_at: Sat, 03 Oct 2020 19:22:38 UTC +00:00, updated_at: Sat, 03 Oct 2020 19:22:38 UTC +00:00>]
So I tried figuring out what to do with it… Granting them to the existing user does not solve anything. Deleting them does not solve anything.
Next step: rebuild the involved topics anew, destroy the old ones, see what happens: unless anyone comes up with a better idea…