Last week I emailed a professor from my undergrad whom I was close with to say hi and inform her that my undergraduate thesis had been published. I am currently in a master’s program and asked her if she would be willing to write me a letter of recommendation for upcoming PhD applications for next Fall (and it is worth noting that she wrote me a letter of recommendation for the program I am currently in). She has yet to reply and having a letter from her would really strengthen my application. Is it in poor taste to resend her an email, or should I move on? Like I said, I would really like to have her letter as part of my applications.