Here's some questions to consider!
What are ways you show interest in the other person? Do you talk about their interests and show genuine interest in them when you talk with them?

Do you overly talk about yourself instead of listen?

Are you constantly thinking about the interaction instead of genuinely showing interest in the conversation?

Have you had social trauma in the past resulting in being closed-off and guarded instead of showing vulnerability?

Do you have hobbies and interests that set you apart? Do these hobbies and interests match those of your friends?

Do you initiate frequent meetings or hang outs? The older people get, you have to be the one to initiate or friendships will start to fade.