trying to keep the box blank unless the other boxes used are filled

Hello,

   I am using this formula which works but I keep getting the "#N/A" in the box until an adjacent box is filled in to give the formula answer. Can someone please assist with having the formula leave the box blank unless the adjacent box is filled, thank you.

Names are used to fill in the boxes which will automatically trigger the box to fill in with a name of the Point of Contact and also a phone number of the POC in the box next to it using another formula in that box.

   =INDEX($AF$2:$AK$19,MATCH($I11,$AG$2:$AG$19,0),MATCH($J$1,$AF$1:$AK$1,0))

Thank you for any assistance