Hey, thanks for the report.
This is a known issue with model selection persistence when switching modes. The team is working on a fix.
As a temporary workaround, you can set the default model for each mode separately. In the model selection dropdown, there’s a setting where you can specify the default model for Ask, Agent, and other modes - then each mode will use its preset model. See an example solution here: Choose a model for each mode - #3 by Artemonim
Let me know if this helps.