To ensure you receive your proof of no-claims bonus, it is essential to clear any existing debts or obligations with your previous car insurance company. This can often involve paying any outstanding premiums, fees, or penalties that may be due. Once all outstanding dues have been settled, the insurance company should be able to provide you with the necessary documentation to support your no-claims bonus.
If you are having difficulty resolving the matter directly with your previous insurance company, you may consider reaching out to the insurance regulator in your country or state. They can provide guidance on your rights as a policyholder and assist in ensuring you receive the necessary documents you are entitled to.