You receive resources if your warehouse is within certain range of your bank and BG bank level.

To avoid this issue make sure that your warehouse is 75% full when doing BG, especially if your bank is 50-100% full.

Also avoid upgrading your warehouse higher than level 22, its impossible to fill it when its higher than level 22

Dear Lord

great tips you received for one of the best bg player of the game so my advice is to follow all of them

i only could add, that getting resources as payout is not an issue if not part of the game and you have to do what he said to try to get the less as you can resources as payouts, although sometimes depending of what you get your bank will be reduced less than you think or maybe nothing.

;)

You receive resources if your warehouse is within certain range of your bank and BG bank level.

To avoid this issue make sure that your warehouse is 75% full when doing BG, especially if your bank is 50-100% full.

Also avoid upgrading your warehouse higher than level 22, its impossible to fill it when its higher than level 22

Oracle said:

To avoid this issue make sure that your warehouse is 75% full.

It is correct that filling your warehouses will prevent resource payouts. 

You will get resource payouts even when you only have 2/3k of bank free but only up to the amount of free space in your warehouses i.e. it wont pay you out more res than you can store, so you won't lose any resource coming back from a BG.

Not sure where the 75% comes from, although maybe they have changed it since I last played BG's, but then they claim to have changed nothings.....

Despite a lot of urban myths on the topic, getting paid in resource is not a major issue. It reduces your bank by the value of the resources, not by more as many people have stated previously. Of course as you are trying to turn resources into troops getting paid in resource is a backward step, so clearly not preferable (just not show stoppingly bad either).