Bot9

The product showed great promise, but a few weeks after the sale in Appsumo they basically abandoned the project. I never got a single response from their team.
The custom actions (they were among the first to implement them) never worked. And since they took away the ability to use their own ApiKey, the quality of responses is very bad.

Among the worst purchases of Appsumo.

It is effectively closed, but without being closed.
A nice way of not disbursing the refund.

Unserious for both the founder and appsumo itself, which should not associate its name with such practices and protect its plus users.