It's simple - you give them notice during local working hours (i.e. not the weekend), that way the customer has time to rectify, and if they don't you can take

It's simple - you give them notice during local working hours (i.e. not the weekend), that way the customer has time to rectify, and if they don't you can take action and have proof of warning them of the consequences of ignoring the notification. If they are having payment issues, it affords both parties time to discuss the issues and see what can reasonably done. It's called customer service - something that Google clearly struggles with.