Two horizontal lines appeared near bottom of screen

The model would have helped. Generally horizontal lines in the picture come from a defective panel and the set isn't fixable, you could try replacing the t-con board but chances of fixing it are slim

The horizontal lines that are showing up on your TV's screen is caused by either a bad cable or a cable that is not correctly fastened to the input and the output ports for the TV and it can cause interference then and the signal and cause horizontal or vertical lines to appear. It could also be the TV"s screen is no longer working and needs to be replaced.

Generally this is a bad panel causing horizontal lines

Horizontal lines on LCD TV,
not usually repairable
plasma may have a corroded or dirty connection on ribbon cable left side of TV looking from the rear

If you wish to get some details; check the site linked here. Pull up older posts.
http://electronicshelponline.blogspot.com/
Line faults & possible causes to LCD & Plasma screen are given with illustrations. You can get an idea about the fault to an extent. Faults to all LCD & Plasma screen are similar, irrespective of its brand and screen size.

Live until more line appear as it will need a electronic board to be replaced.
Is the line black or colored ?
how thin and where on the screen?

https://www.youtube.com/watch?v=j7vl7-vZEL8
see attached video of another model for help. but the decision is yours

Samsung LN46B650 Thin Black Horizontal Lines - Forums - CNET

www.cnet.com > Forums > Samsung

CNETI'm experiencing thin black lines from the top of the screen to the bottom. ... by babes808gpa / January 15, 2010 1:42 AM PST ... lines are about 1/4 inch apart from top to bottom of screen. starts on the right and about a 1/3 of the way toward the ...have the exact same problem, my lcd tv has multiple lines are horizontal it ...

Faulty HD- LCD - LED TV - Horizontal Lines STRIPS on the ...

? 3:05
https://www.youtube.com/watch?v=KiqJuMiEiak
Jun 8, 2013 - Uploaded by Sameh Moustafa
Faulty HD- LCD - LED TV - Horizontal Lines STRIPS on the picture SOLVED .... I just have one black line ...

TV Repair Help for Vertical & Horizontal Lines on Your TV ...

? 2:47
https://www.youtube.com/watch?v=b0sI7LB4cZE

Not good. You may have a tab failure. A repair shop may be able to diagnose and repair this, but most likely the lcd panel is broken. The panel is the most expensive part of flat tv's. A new panel will cost more than a used tv.

sounds like your panel is going bad. usually not economical to repair.

Open up the TV and unplug and re-plug the connectors to the circuit boards. This is most often caused by a poor connection of the circuit board connectors.