Screen Burn In on ROG PHONE II

[Aruna]

Please tell us some basic information before asking for help:
Model Name: ZS660KL-1A017IN
Firmware Version:WW_17.0240.2007.27_0
Rooted or not: Not rooted
Frequency of Occurrence: Noticed 1 small patch today & 2 discolored lines on white background
APP Name & APP Version (If your issue relates to the app): No
In addition to information above, please also provide as much details as you can, e.g., using scenario, what troubleshooting you've already done, screenshot, etc.
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Hi, I'm Aruna. I'm using Asus ROG PHONE II 8GB Indian version for past 9 months. I use phone generally for gaming, but apply screen pressure cautiously.
Today I suddenly noticed a white patch on top right corner & 2 blurry lines appearing on mid of right side screen. Its noticeable on white screen.
On Google search, I noticed the symptom is relatively called as 'Screen Burn In', which is common in AMOLED screen. One of my friend told he used Samsung Galaxy Note8, which had same issue, the display gets more spots once the issue appears & he got display changes from service center.
Is my issue similar? Phone is under warranty & no single scratch, never dropped or mishandled. I'm visiting service center tomorrow anyway.
ANY SUGGESTIONS REGARDING ISSUE?

[Gustav_ASUS]

I would need to look at a screenshot before I can make a comment, but it's possible you have burn-in.

[Aruna]

I don't have another phone to take a photo, but it's similar to a droplet of water dropped on screen. Images behind the spot appears blurry.

[Anders_ASUS]

I suggest you take it to a service center and let them have a look at it. Only they can determine if it's a warranty case or not

[Aruna]

I took the phone to service center in Delhi at Nehru Place. They took the phone for repair on 09 Sep 20 without asking any questions and only verified bill. That's good.
I had to wait for 7 days to get my phone repaired. Just got it today. They don't have online update regarding issue like Samsung, that's a downside.
Regardless, I got my phone with newly replaced screen.
Another thing, IS THE BATTERY ALSO REPLACED during DISPLAY CHANGE?

Because, I notice the battery history isn't available & after full charge, it takes 10 mins to get down from 100% to 98% as opposed to older time of some 3~mins.