Rest Api failed to publish 15k character word post content

this is working fine:

$json_data = [ 'title' => $post->title, 'content' => $post->title, 'status' => 'draft', ]; $response = $client->request('POST', "/wp-json/wp/v2/posts", [ 'json' => $json_data, 'headers' => [ 'Authorization' => 'Basic ' . base64_encode($username . ':' . $application_password), ], ]); return "working fine"

but this code failed when i put post content as 15k character lentgh

 $json_data = [ 'title' => $post->title, 'content' => $post->content, 'status' => 'draft', ]; $response = $client->request('POST', "/wp-json/wp/v2/posts", [ 'json' => $json_data, 'headers' => [ 'Authorization' => 'Basic ' . base64_encode($username . ':' . $application_password), ], ]); return "not worked"

Showing the issue is

Server error: POST https://example.com/wp-json/wp/v2/posts resulted in a 500 Internal Server Error response: {"code":"db_insert_error","message":"Could not insert post into the database.","data":{"status":500},"additional_data":[ (truncated...) 

• This topic was modified 2 minutes ago by imranbru99.

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