Purple & red flickering lines on 13in 2018 Intel MacBook Pro

Looking for suggestions and potential fixes. I have an Intel Macbook Pro 13-inch, 2018, Four Thunderbolt 3 Ports.

I unfortunately can't show you what it looks like since it's just in the display, but it's 5 columns of dashed lines of purple and red. I see some blue too. It kind of pulses on the screen.

Here is what I've tried to do so far:

• Already reset the NVRAM and SMC - didn’t fix it
• The temperature of the Macbook is fine (around 50º C)
• Put it in Safe Mode and lines are still there
• Ran Apple Diagnostics and it said no issues found
• Also took a screenshot, and the lines don't show up, so it’s a display problem
• My Mac is already up to date (Sonoma) so no graphics card driver to update

It does say Service Recommended for my battery but I think it's been like that. These lines interestingly showed up after using a 7 day trial for the app Iris (protects your eyes). Turns the screen red at night for better sleep. Not sure if that had to do with it.

I think there might be something loose with the display cable (?) but I can't find a youtube video with my particular model. I'm not sure if this can be fixed myself. The last digits of the laptop serial number is JHC8. Let me know if you need more info!

My coverage/warranty has expired.