Cold Emails not Getting Opened- What's Wrong?

I have a chrome extension which tracks email opens, and I've sent out 15 emails to alumni this week, and only 3 people have even opened my emails, much less responded. I got to a target school as well and received the template from an upperclassman who said he had a ~20% response rate, so I was wondering if it has something to do my subject line or time I send it out? I typically have my emails scheduled to send ~8 to 9 am. Would love any feedback I could get.

Subject: school Second-Year Interested in Firm Opportunities

Body: 

Dear XX,

I hope this email finds you well! I am currently a second-year at school majoring in economics who's interested in pursuing a career in investment banking at Firm. 

I was applying for Firm 2022 Analyst Program and came across your profile on LinkedIn while doing some research and would love to learn more about your experiences in the industry. I'm sure you're very busy, I was wondering if you'd be willing to have a brief 15-20 minute chat about your experiences at school along with [personalize] - I can send a Google Calendar invitation if needed. Please let me know if there are any times that work for you. I have attached my resume for your reference. 

Thank you so much and stay safe!

Best,

the.turnip.overlord