When I select certain regions of the sketch and try to extrude them I get an error message.
Model is in the attachment.
Since you have not specified what you are looking to model or what is the intended outcome, i guess you are trying model as below.
If my guess is correct as show in the image below,
The you need edit the sketch to make the 3 regions, modify as below,
I have attached the file for your reference, hope this helps you.
Retrieving data ...