‘07 Corolla CE not starting

Hello, I’ve been having issues with my 07 Corolla CE not starting. December of last year is when it first started happening. Sometimes the dash lights come on but the car won’t turn over. Sometimes no light comes on. When I do turn the key you can an hear electric spark sound. I thought it was the battery. I checked if I was getting the proper voltage and it was. I did clean the connections and that seemed to help. Took it to a mechanic to see if it was the starter or solenoid and they couldn’t find an issue. About a month ago had the same problem. Checked voltage to the battery and it’s fine, connectors fine. After that one day car ran fine. I have noticed over the last couple days it’s happening again. After a couple try’s the car turns over. Yesterday and today the car won’t turn over at all. Any suggestions or help would be greatly appreciated!