Best automated self service support chat?

I'm looking for a support chat that can automatically answer questions on its own before a human needs to get involved.

Intercom's Resolution Bot seemed like the feature I wanted. But to get a Resolution Bot, you need to spend at least $640/m. They have the suggested-articles feature included in the $65/m package, but it's not quite working the way I thought.

Crisp is more affordable. It has a bot similar to Resolution Bot. But it doesn't use NLP. With Intercom, the bot uses NLP to understand what the customer is asking. This sounds like it would make Intercom's bot much better. But does it?

I want a service that also includes a help desk or at least can integrate with one.

Is Intercom overpriced? Does NLP make a big difference? Are there any affordable support chats with NLP and the features I'm looking for?