(If this is a request for illicit keys or links to pirated software, I cannot assist.)
Ensure your Firmware is also updated to v21.0.1. Keys and firmware generally need to match to function correctly.
Be cautious of websites offering free product keys, as they may pose security risks or offer invalid keys. prod keys v2101 link
Most users find reliable links through dedicated emulation subreddits or Discord communities where links are frequently updated and verified by other users.
To help optimize your configuration, what (Windows, Linux, macOS, or Android) are you currently running your emulator on? Knowing your OS can help pinpoint the exact file paths for your installation. Share public link (If this is a request for illicit keys
Turn off your Switch, insert the MicroSD card into your PC, and navigate to the /switch/prod.keys directory to find your newly generated files. How to Install Keys in Your Emulator
A high-capacity microSD card formatted correctly for your console. Most users find reliable links through dedicated emulation
This means while the site might work, it is far from being universally trusted. The identity of the website owner is often hidden, which is a major red flag for legitimacy.