Share your experience!
What exactly are you doing? Settings - lock screen and security - tap on the first option (screen lock), insert your pattern and you will get several options (none, swipe, pattern etc).
Hi @Ananta_purohit,
I'm sorry to hear that you are experiencing this with your Xperia XA.
As @alexdon said you should be able to change your screen lock pattern if you go to: Settings > Lock screen & security > Screen lock. You will need to know your current pattern to be able to change it to another pattern or type of screen lock.
If i misunderstood your question or you need help with anything else let me know!