What are the actual differences between the free and paid versions of Amelia?

Managing website appointments with Amelia Free Edition has recently encountered a problem: some of my clients and my virtual assistants have given me feedback that Amelia could not be loaded.and on my end (including the WordPress backend) everything is fine.

There's a question at the moment:Free vs Paid Version Differences

Officially, the standard version is shown to have seemingly the same functionality as what I have, but are there hidden limitations in actual use?

Is the loading issue related to the free version? For example, server request limitations, compatibility optimizations, etc.