Hi Tifany. I'm not from the dust team but I believe I have encountered this problem several times. Most of the cases are when I use an assistant with access to certain tools and then switching in the same thread to another assistant with no access to tools with the same name.
The easy fix is to tell the assistant in the chat tread to not use tools in the request if you are using it yourself.
The other much better fix is to name the tools yourself instead of relying on the auto name (eg search_data_sources_1 etc..). And to specify to the assistant in the system prompt which tools it has to use and insist that it doesn't use any other tools.
I hope this helps.
