How are you writing your emails? Make a list of your interests and match it to professors and their area of research. Be clear when you email them as in:
Introduce yourself succinctly and explain what your technical/major related background is, what your interests are (ideally match this with the lab). Perhaps related classwork/projects would fit here.
Read up the research the professor/lab has done, even if you don't understand everything. Mention specifically what papers/projects interested you in the email.
Ask to have a conversation with the professor, i.e "I'd like to learn more about x and the lab's work in y, would you have time to meet to discuss this blah blah".
Overall, keep the email short but make sure each sentence has a purpose. You might not always get a response, or maybe they won't have space and only have time for a conversation. But hey, you at least made a connection and can always try another professor after. Maybe stagger your emails from your first pick to second etc, and you could title it as something related to 'interested in undergrad research blah blah'.
Worst comes to worst, be specific about the classes that you take in an upcoming semester. Pick professors whose labs you want to work in and work hard, go to office hours etc. I can't see you failing in that scenario. Depending on your major, perhaps you could also work on a personal project during the summer and be able to showcase the project/skill in the upcoming school semester.
Lastly to add I'm not a professor, but I maybe wouldn't hire/accept a summer-only student unless they already had some skills. Its just a fact that when you're earlier in your major, it takes longer for you to get up to speed and running. Something that could take you a week will take someone a day maybe. Professors know that and are willing to invest in the student, but you in turn should be willing to return that investment, and show that you are willing to work during the year etc