Masking not working in premier pro

[Miss Angela23418227hen8]

Hello, i can't seem to make the masking tool to work correct In premier pro 
When i make an adjustment, , the adjustments will be applied over the whole clip and not just the masked part
Is this a bug or am i doing something not right?
Help please... 😘 thanks everyone 

[Ann Bens]

Post screenshots of the setup. Now its just guessing.

[Miss Angela23418227hen8]

Thanks it is now sorted