I believe its that last door of the Big Dig Quest where you meet Farenheit. Mel enters the door first followed by Bobbi No Nose.

I approach the door to enter it but it doesn't allow me to press "A" to enter the door. I've tried reloading from saves a various times etc but still the same outcome. How did I get out you ask?? Funny enough I was able to partially enter the door where the door turned black which glitched me outside of the map from there I was able fall off out of the mapped and it teleported me to the beginning of the Quest. If I go through the Quest again will I be able to complete it? Will there be a patch for this??

Thanks

The last door is rather tricky because it doesn't work like the rest of them.

You need to speak to Mel and select the "I'm ready" dialogue option. No other choice will work. Once selected, the eyebot will break through the last door.