Some Audio/Video (A/V) receivers have a feature which allows you to turn off a specific input. If the input is turned off, it will be skipped when cycling through the inputs using the FUNCTION button on the remote control.
If you cannot select one of the inputs on your receiver, or the input is skipped when cycling through the inputs when using the FUNCTION button on the remote control, check your menu settings to make sure the input is not turned OFF or set to SKIP.
Information on the features and capabilities of your receiver is available in the manual included with your product. Manuals are posted on your model support page.