If while publishing a template, the said error occurs, then make corrections to the current template or to the template that the bot mentions.
Once the corrections are made, you can try publishing again.
Here is a demonstration of the same.
Facebook does not allow the use of inbox feature at high traffic, incoming or outgoing. Hence, it gets disabled every time a campaign is sent. As at such high volumes, it is not possible to reply back manually. You can read about it here: https://developers.facebook.com/docs/messenger-platform/send-messages/high-mps/