I'm going to block a girl on my boyfriend's phone.
Is there a reason you are gonna block this girl?
Yes, she was pretending to be me when she wanted to meet my boyfriend.
While it is understandable that you would be upset at that woman pretending to be you, you should not touch and block someone your boyfriend's phone as that is snooping and a breach of privacy. You should talk to your boyfriend about that woman's malicious behavior and reach an agreement together, as a couple, on what to do next.
I'm not snooping, I'm just trying to be a good girlfriend. I don't care about her anyway.
I'm glad you don't care about her, and I understand you're just trying to help.