This is so strange. I had a lanyard code and the code from here. I got tickets on Thursday and didn’t have to enter any code.
VIP (and platinum) seats don't generally seem to require a code most of the time for this and past tours? Though sometimes early in the presale you might have to put a code just to get into the sale. (But if you are presented with a list of all the presales, if you deselect everything but the VIP you can usually get in.)
For the non-VIP GB tix, when we were in the mess of trying to get a ticket it was hard to tell what was happening, but in "testing" it later I found if I went in without a code (fresh browser) and I clicked a 'locked' seat that asked for a code that same seat accepted both the lanyard and the Live Nation code.