Please follow the below steps to enable/disable the WhatsApp Chat + Abandoned Cart app:
Login in to your Shopify admin
Go to the App list page
Select/Click on WhatsApp Chat + Abandoned Cart
Click on the “Enable” button if it shows Enable to Enable the App.
Click on the “Disable” button if it shows Disable to Disable the App.
For a quick view of all the above steps, please check the below image.