Limitation of charters numbers and wrong counting


How do you comand ChatGPT 4 to write article about flowers that has a minimum of 15000 charters not counting spaces and special characters?
My current record is 17000 charters in one continuous reply but it stopped working.
Also, in ChatGPT charters count was desable few days ago so 50 ChatGPT 4 replays are waisted in 90% of cases.