I thought I had a ticket all sorted through BA in South Africa but a phone call tonight put paid to that. They were telling me I was breaking some of the rules despite the online tool saying it's a valid itinerary.

JNB-LHR, LHR-LAX-DFW-SEA-DFW, DFW-LGA, LGA-DFW-LAX-HKG-BOM-HKG-DEL, DEL-NRT-SYD, SYD-HKG-JNB

Can someone point me to where I've apparently gone wrong? I guess to keep the ticket I'll have to modify the itinerary.