WooCommerce Fixing issue with one of payment methods

Cash on Delivery was setup as Cash on Pick Up payment method. Was supposed to only function when pickup as delivery method was selected. We decided to disable this function. So that its no longer available. However after update, the following issues have occurred:
- This method is now visible even when disabled in the backend
- This method now visible for either Delivery or Pickup option

We would like to disable this and for it not to come up after WooCommerce update. Ideally to implement the solution using the Code Snippets plugin for easy activation and management and add a custom hook to permanently disable "Cash on Pickup."