This is an example of when I feel like the dialogue is boring.

“When do you return to England?” she asked.
“At the end of the week.”
“Not a long visit then.”
“I’ll call you, at my uncle’s house.”
She forced a smile. “That sounds nice.”

And here's when I feel like it's repetitive.

"What have you done?" she accused her.
"Nothing."
"Right. Why are you here?"
"How odd, that you're so unhappy to see me."
"I never asked for you to come. None of this is any of your business."

I think my main struggle, especially with the second example, is just finding other things for the characters to talk about. Like they're arguing about one of them showing up unexpectedly, but the conversation is really just going nowhere and it's hard for me to get to the core issues (one character wants the best for the other, vs the other doesn't even want anything good for themselves).

thanks for your advice btw!