Is a telephone call for the unpaid invoice: a sales call or a debt collection call?
In my view, a telephone call for the unpaid invoice is always a sales call. The reasons for this point of view include:
1 obviously the first reason is - a sale is not a sale until the invoice is paid;
2 the customer maybe on the stop supply list and therefore your salespeople can not sell them anything;
3 there may be a problem you are not aware of - and once you are aware, you can do something about it; and
4 even if the call is about debt collection, you should always take the approach that you are selling your business's right to be paid and there are ramifications the customer may not be aware if they do not pay.
It is for these reasons, it is always best to take a 'sales like' approach to every telephone call for the unpaid invoice. The days of demanding payment are long gone anyway. Therefore you might as well take the approach and have something positive to "sell" to the customer.