What is the ruling on not visiting one's paternal uncle and communicating with him due to shyness and customs and traditions, despite being able to greet him when seeing him by chance?

If you communicate with your relatives through greetings and conversation, then this is considered maintaining kinship ties and you are not considered a severer of ties. Scholars have clarified that kinship ties are maintained through conversation, even if it's just by exchanging greetings. Visiting, calling, and inquiring about their well-being are recommended if possible. And know that discord among relatives is a serious matter. Allah Almighty says: "So would you, perhaps, if you turned away, cause corruption in the land and sever your ties of kinship? Those are the ones whom Allah has cursed, so He made them deaf and blinded their vision." The Prophet, peace and blessings be upon him, urged the reconciliation of disputes, and described discord as "the shaver" [meaning it shaves away one's religion]. One should seek the help of wise and rational people to strive for reconciliation, along with supplicating to Allah Almighty for its achievement.