OK, I’ve found the document that it’s erroring on. I’ve taken out some other fields as it contains sensitive information, but this is the content field that’s giving me the error.

array:8 [▶
  "content" => array:3 [▶
    0 => "10 Km"
    1 => "Runthrough Chase The Moon Battersea Park 5k & 10k"
    3 => "Transferred"
  ]
  "post_date_timestamp" => 1690786080
  "id" => "2719427"
]