In the future if you have any retroarch questions or problems post about them on the dedicated retroarch thread https://gbatemp.net/threads/retroarch-emulation-thread-nightly-builds-included.400913/ most questions or problems people have are already answered on there and if you do have a new problem then you have a bigger chance of someone being able to help. Not only that but Aliaspider the developer of retroarch 3ds goes on there and answers questions and problems so who better to ask than the man developing retroarch.