Grey lines/ bars at the bottom of iPhone 6

hello, i just would like to ask any help about the current status of my iphone 6. basically, my iphone 6 has “grey bars/ lines” at the bottom, refer to photo below. the “bars/ lines” appeared on december 26, 2021. my iphone 6 wasn’t drop or knock on anything when the day that the “bars/ lines” appeared that’s why i’m seriously concern. in addition, there’s no problem at all about the screen specifically on the area where the grey lines/ bars are as i can still touch it perfectly fine and it is responsive. however, it has also a black spot/ circle on the lower left bottom, but i think it’s getting better as it’s becoming smaller each day. lastly, i noticed that sometimes the lines/ bars are turning into different colors.

i guess the problem is how to get rid of the lines, because i think the black spot or circle is getting better as it is becoming small each day and when i charge the phone.

please, to those who have the same problem on their phone but already got if fixed, i would highly appreciate it if you could share any information/ advice/ help to resolve my problem.

thank you so much and please stay safe everyone. <3

p.s. please excuse the super low quality photo as i’m using my old phone just to take it for your reference. :)