Overseer sending a blank message on discord when new movie / Tv has been added to plex - discord

Question

I have overseerr set up to send a message on discord when a movie / Tv show is available on plex. A few months back it stopped working, just had not had time to look into it. This is the default json in overseerr
{
"notification_type": "{{notification_type}}",
"event": "{{event}}",
"subject": "{{subject}}",
"message": "{{message}}",
"image": "{{image}}",
"{{media}}": {
"media_type": "{{media_type}}",
"tmdbId": "{{media_tmdbid}}",
"tvdbId": "{{media_tvdbid}}",
"status": "{{media_status}}",
"status4k": "{{media_status4k}}"
},
"{{request}}": {
"request_id": "{{request_id}}",
"requestedBy_email": "{{requestedBy_email}}",
"requestedBy_username": "{{requestedBy_username}}",
"requestedBy_avatar": "{{requestedBy_avatar}}"
},
"{{issue}}": {
"issue_id": "{{issue_id}}",
"issue_type": "{{issue_type}}",
"issue_status": "{{issue_status}}",
"reportedBy_email": "{{reportedBy_email}}",
"reportedBy_username": "{{reportedBy_username}}",
"reportedBy_avatar": "{{reportedBy_avatar}}"
},
"{{comment}}": {
"comment_message": "{{comment_message}}",
"commentedBy_email": "{{commentedBy_email}}",
"commentedBy_username": "{{commentedBy_username}}",
"commentedBy_avatar": "{{commentedBy_avatar}}"
},
"{{extra}}": []
}
In the logs, I see this error code 400 and 50006
Can anyone advise on how to fix the code? Many thanks