I can't access a pin for an boost-buck converter because is in the middle of the part

[BernyZa897UH37]

I'm trying to route an the only airwire left but the other pins in the part prevent me to access the pin even if I try to go the bottom layer I can't access it because I don't have a way to come out. Is there another way to access this pin?

[one-of-the-robs]

Your board layout as a whole gives the impression of a fairly low-spec fab - two layer with 10mil traces and 0.6mm minimum drill? If so, that's not suitable for a high density BGA part like that. Can you not get the chip in SSOP/SOIC or similar? BGA is generally a pain and to be avoided unless you really need the high density (and are designing a ten-layer PC motherboard or the like)