Guild transfers seem to be functioning incorrectly right now, but they're working on figuring out what is wrong.

We are currently investigating an issue that is resulting in some guild transfers via the /transferguild command to not complete. This is one of our highest priorities currently, and we are working to resolve it as quickly as possible. If you are experiencing this issue, we ask that you submit an in-game CSR Appeal so that we can assist you. Please understand that the process to correct this issue manually takes quite a bit of time, so we thank you in advance for your patience. For more details about the transfers, please see this post.