Graylog doesn’t automatically pull the IP address out of the message, you need to either use Extractors or functions in the pipeline to do that. Once it is extracted to a separate field then its possible to geolocation going.
Other that saying that you followed documentation, you are not giving us that much information to help you… I would suggest reading through This document and/or this document to figure out how to give relevant information when asking a question and even showing your work for what you have tried. The net result would be more complete answers that may help you achieve your goal faster…