How do I get any clients with 1to2 days availability?

It's tough with that availability. Rover is by far the best platform, but other platforms are better for picking up "walks on demand" and more similar to how an Uber driver can just turn on the app and work when they want to. However, I think you should keep your Rover profile and use it as a great professional reference with those testimonials. In the future, your schedule may change and you might be able to do a lot more through Rover.

I hate to say this but with your current availability, it's highly unlikely you will ever get any clients on Rover. Most dog walking clients need you multiple days of the week. Best of luck I hope it works out for you