When using an IVR, the system will allow you to use number keys to enable a lead to put themselves on the DNC list. By allowing the lead to place themselves on the DNC, you can weed out undesirable leads and only dial on the desired leads.
From the Dashboard, go to Call Center and access Call Center Queues.
Create a new General Queue for DNC (Go here to know How to Add a Call Center Queue)
After creating a new Queue, go to settings and access the Call Routing tab (Go here to know How to Edit Queue Call Routing Tab). In the Call Routing tab, look for Drop Call Settings section, set the Total Max Wait Time Sec to 1. Change the Drop Call Destination to Status call to DNC and Hangup.
We need to create an IVR to upload a voice message giving instructions on how can a lead add their number to the DNC List. Go to Phone System and access Interactive Voice Response, click on the settings to modify your IVR. (Go here to know How to Create an Interactive Voice Response)
On the IVR settings create a new IVR Entry, select Call Center Queue for the IVR Destination and select your DNC Queue as route, then click Apply Changes to save the settings.
Go to your Inbound Number settings (Go here to know How to Edit Inbound numbers). Set the Route to your IVR. Also, set up your Inbound Number's Lead Handle Method. List Search Method should be set to Search entire system, otherwise create new lead in the default List. Set the Number Search option to Phone & Cell Phone & Work Phone. Lastly, select the List you want to use as Search / Default List.
You may also want to turn on your Inbound Number's DNC Handle Method to have the system block inbound calls from leads that are already in your DNC List. Set the Search Method to Account Wide. Set the Route Call To Terminate Call and Hangup.
Note: If you have an existing IVR and you added this feature, you need to re-upload a new IVR audio menu stating which key to select to have the lead's number be added to the DNC with the new key selection for DNC.