Erm, no you didnt - TTIG not yet supported in V3 and needs to be set up and used in V2 1st! (Migration for this to be announced sometime later)
Well it comes down to RTFM - if a new user you really should have started by reading the available docs and using Forum Search, before diving in… where you would have found lots of posts covering above
and also covering…
Why you SHOULD NOT DO THAT (including the clear warning messages that tell you not to delete on the console, that you must have ignored!)
I see you joined last summer and have looked at many posts, albeit quickly given total reading time logged, so not quite a new user…had you not seen any relevant posts along the way?
At this point your best option, if now registed in V3 console, it to be patient and wait for the switch-on of TTIG V3 support at which point, hopefully your TTIG will automagically appear in the system or atleast should be recoverable…
In the meantime, though not available to you in the console it may well still be receiving and forwarding messages to the V2 back end and through Packet Broker to V3…do you have functional nodes & applications? If you do you may see traffic coming through if you leave it live (is green led on top on & stable?)…GW EUI will show in message metadata in V2 device/application console or an anonomised version if app in V3 coming through the PB…