If you just replaced the right fader bank, you didn’t solder the bank’s “pads” to assign the new hardware to the correct fader bank (left or right). I went through the exact same thing when I replaced one of our fader banks. See this post for more information: https://community.allen-heath.com/forums/topic/replacement-fader-bank-not-recognized-by-console
If you didn’t just replace a fader bank unit, then there has likely been a corruption of the firmware or an actual hardware failure. You can try to reinstall the firmware to see if it fixes it. If not, then it is probably time to contact A&H Support directly and/or contact your country’s authorized distributor.
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