Are you able to get a screen shot of the configuration so we can look over your configuration. Additionally what are the make/models of the main router and the access point or router acting as an access point repeater?
*Some devices dont communicate with others to act as repeaters, we can rule this out if we know what make/model of your wireless devices are to verify that they will work together correctly. I had a Linksys router for example that refused to work with a D-Link as a repeater because the Linksys I had needed to be paired with another Linksys in order to sync correctly as a repeater.