The important thing about the telephone demand is silence. This is called Strategic Pause in the West. It is common to negotiate things but the point is to let the other party talk a lot.
In terms of collection, the more the other party talks, the easier it is to find out the contradictions of excuses. Do not start talking just because the other party is silent. Human nature is that they cannot stand the awkwardness of silence. They frantically start talking to fill the silence.
When the debtor starts talking, listen carefully to the debtor's talk and just attach a commitment. The most important thing in the commitment is to set a deadline. This is as stated earlier.
Another important thing is to let the debtor promise you. Humans tend to keep their own commitment. Therefore, it is also important to have the debtor promise you a specific date and time or the amount of money. For those who cannot speak for themselves, offer a concrete promise is to make an unreasonable date and money request from here on.
When a debtor tells you, “We cannot pay in full. We cannot pay today”, then switch immediately to “Then how much can you pay? Then when can you pay? “The debtor has no choice but to reply.