Positional Tracking failure on zed2 with gnss fusion. Need help finding gnss_frame parameter

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I am using rtk gps that publishes messages of type sensor_msgs/msg/NavSatFix on the topic /NavSatFix. I am also using a zed2 camera that subscribes to this topic using ros micro agent. Now when I run the zed2 node, I am getting the following error: "Fusion error: FAILURE". I believe I am using the wrong geo tracking parameters, specifically the gnss_frame (TF frame of the gnss sensor). How can I find the gnss_frame of the sensor to set it correctly in the .yaml file? My parameters currently look like this:

gnss_fusion_enabled: true # fuse 'sensor_msg/NavSatFix' message information into pose data
gnss_fix_topic: "/gps/fix" # Name of the GNSS topic of type NavSatFix to subscribe [Default:"/gps/fix"]
gnss_init_distance: 5.0 # The minimum distance traveled by the robot required to initilize the GNSS fusion
gnss_zero_altitude: false # Set to `true` to ignore GNSS altitude information
gnss_frame: "gnss_link" # [usually overwritten by launch file] The TF frame of the GNSS sensor
publish_utm_tf: true # Publish `utm` -> `map` TF
broadcast_utm_transform_as_parent_frame: false # if 'true' publish `utm` -> `map` TF, otherwise `map` -> `utm`