To check who logged into your Hostinger account, navigate to your hPanel, click on the profile icon in the top right, and select Account Activity:
There, you can see information about the previous logins, including the date and time, device, location, IP, and login method:
What to Do if You Don't Recognize Some Logins?
If some previous logins don't look familiar, or you suspect that someone has gained access to your account, you can always log off from all the devices and change the password in just a couple of clicks. Click on the Don't recognize a device? button at the top of the page: