I had warranty left (since I bought my MBP 2016) from JBHifi Australia and proceeded to get it repaired when I had this problem. Took about 7 weeks to repair for me and luckily it was under warranty, otherwise the parts used totalled $523.75AUD. I’ve been using it again for another month now and these lines has began to appear again. So I honestly don’t know what to do, repair seems to do absolutely nothing and I’m too poor to either get a new MBP (for editing purposes) or get another repair.