Why can't I enable the auto bidding option? As soon as I do it, it toggles back to off after saving the scanner.

If your scanner turns off every time you try to enable it, check your autobidder tab - there is a high chance that your scanner detects 300 job posts per month at the moment.

For more information about the 300 jobs per month limitation for a scanner and how you can resolve it, take a look at 🙅🏻‍♀️ 300 jobs / month limitation article.