I've tried to edit bot's message which was sended about 2 hours ago and got this error and supposed that this message so old for editing that it is unable. Then I've tried to edit another message which was sended a little later and it was successful. But after this I've tried to edit one of recently sended messages an got this error one more time. Now it seems like request's results is random.
What does it mean?
Here an example of my POST query:
https://api.telegram.org/bot{token}/editMessageText?chat_id=12345&message_id=370&text=New text
And here result:
{
"ok": false,
"error_code": 400,
"description": "Bad Request: message not found"
}