The Gateway ID on the console is for your personal identification of your gateway. The Gateway EUI is, confusingly, called the gateway_ID in the conf file.
There is no way that your EUI would start FFFE - anytime we use FFFE, it goes in the middle. And it goes on public record so there is no point ***** it out.
Given the made up EUI, can you tell us what gateway you own - brand and model please.
It’s not clear if you tried downloading the configuration file from the console as suggested?
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