maybe it's because the gas is too small that makes the transaction get delay for 2 days because as far as I know, from the normal gas, I always increase 20k or 30k to send and it's no need to wait too long to receive in my wallet. so I think before you want to make a transaction, make sure that you use higher gas so you don't have to get any delays.
the last time my friend sent me ETH it did took a couple of days but Yes, I think it's a gas issue because everyone want's to send coins with a minimum of gas as possible.
I think my friend only gave a little gas as a result of couple of days of queuing and processing.
it should be set on higher amount of gas so that miners will then set it to higher priority than other queue.