You're hooking a string I believe?.. you should consider rechecking your codes and offsets.
Also make sure you're actually using ARM64 in your codes, and another thing is don't put arm64 in arm7.
If you're using LGL's mod menu template, it's not for newbies despite that his menu has a ton of features to use.
If this seems complicated for you, don't bother even trying to ask for help. There are many tutorials, so spend your time by reading and watching tutorials.