It may be rare to find folk with this exact setup but I always try the non-4K UHD port (most consumer products are only UHD, not 4K.)
They usually have an answer or check firmware versions all around.
I am setting up a new LG 79UF7700 4K tv to a new Marantz 5010 4K video receiver.
The on-screen Marantz info. is displayed during most functions, but is not displayed for tuner, or internet radio.
Short of hooking up a second tv to the Marantz to see if this info. is displayed properly, do you have any suggestions.
Is there a setting on the LG TV that needs be changed?
Is it a hook-up problem? Cable type, cable location?

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