How to completely disable light-locker and replace it with GDM lockscreen

I am using cinnamon and I really like it but the only problem I have is I do not want light-locker every time I do ctrl alt + l, I want the **gdm** lockscreen to show when I press those keys. I tried to disable the **lightlocker systemct**l but it doesn't have one. How do I get rid of it? I did install **gdm** just want to make it replace **lightdm** completely.