Refuses to say please and thank you
Before You Begin
Pause and breathe. Even if this shouldn't be happening... accept that it is and embrace it with composure and calmness.
Calmness is the only way forward because without calm, there is no possibility for receptiveness and connection. Your child won't give to you any more than they see from you.
Never forget that a strong connection is fundamental, as there will be no correction in them if there is no connection with you.
The Core Problem
They don't understand why these words are used.
What Will Make It Worse
Reacting with frustration, scolding, or negative comments about their manners will worsen the situation and do nothing to make them care or cooperate.
What The Child Needs
1. To learn why we use those words: Teach them that there are many reasons why we say please and thank you. It is our culture's custom, it is polite, it shows gratitude and respect, and it makes a short special moment where the person and you feel good together. Since everyone uses these words, we also get all of these good things directed back towards us when others are polite. This back and forth makes everyone's days more pleasant.
2. To learn when we use those words: Explain to the child the situations where politeness is both expected and appreciated. If helpful, do role-play where the child can practice identifying on their own when a please or thank you is needed. Saying these words to them in a role-play situation will make them feel good and help to reinforce their significance.
3. Positive reinforcement: Give praise when the child uses polite language as you discussed.
How To Have The Conversation With Your Child
Find a moment when you and your child can sit and chat without any distractions. Try not to make the conversation a lecture, but rather feel like you are passing down important knowledge to them, like your parent did to you.
Share with them that it's time they really understood why everyone says please and thank you to each other.
Talk through points 1 and 2 under "What The Child Needs". The younger the child the more they will enjoy doing the role-play in point 2.
In the days following this shared experience of growth, praise them as they act on what you two talked about.