Did you purchase a system after July 17? If so, you should be eligible for an upgrade. Numerous reports from consumers indicate that is allowing those original Switch consoles to be exchanged for the recently-released model with improved battery life.

from https://nintendoeverything.com/original-switch-systems-bought-after-july-17-can-be-exchanged-for-latest-model-with-improved-battery-life/
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