Seat belt issue
The problem is in the part which the seat belt buckles into. There is a switch inside that is toggled by the buckle which sends the signal for the light and beeper to turn off. It is faulty, perhaps it is just age and use which did it in, but maybe someone spilled a drink in it. Just get a new switch from a Honda dealership parts department for a a few bucks and install it yourself, or have someone do it for you, it only takes a few minutes.
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