How to fix a SIM card reader in Apple iPhone 6 plus?

May have damaged or bent pins when fishing out a card lmao…

Needle and lots of patience

Step 1: give your iPhone to your technologically impaired grandma.
Step 2: buy an android.

Simple. You don't. You replace the SIM holder instead.

You take the phone to a repair centre and pay them to do it, or you order the part from an online retailer and fit it yourself after watching a few online video guides: if you've never done it before then you have a high risk of also damaging the ribbon cables to the phone screen.

The problem with a DIY fix is that your question suggests you are not sure that the fault is a damaged SIM holder module, so you might end up wasting time, money and damaging your phone for nothing. A professional repair centre will have the tools and skills to correctly diagnose the cause of the fault enabling them to make the correct repair at the first attempt.