You owe them a sincere apology for any misbehavior or rudeness on your part. And promise not to repeat the same mistakes. Once you have done so, you need not worry even if they fail to respond to you positively. The fact that they do not do so should not absolve you from your duty to be kind to them and serve them honorably as best as you can.
The Prophet (peace be upon him) is reported to have told one of his companions: "To join relations with those who sever relations with me, to forgive those who offend me, and give those who withhold favors from me."
When another of his companions came to him complaining about his relatives saying: I have blood relations no matter how kindly I treat them they act rudely towards me; shall I stop being kind to them? The Prophet replied, “No, you should continue to be kind to them, and God will be your protector as long as you do so.”
In conclusion, I would urge you to continue to treat them as kindly as you can regardless of their persistence in their failure to respond to you positively.