It helps to specify what things you’ve tried, so we can suggest things you might have missed.
Usually this ends up being either a wifi issue or a problem with the black cable. Don’t assume it’s not wifi just because nothing else in your house has problems with it – the GF is particularly sensitive to irregularities that don’t bother other appliances.
Here’s a list you can check to make sure you haven’t missed anything in your troubleshooting:
