Problem challenging someone

I am trying to challenge a player, who wants me to challenge him, to a 3-day time control game.  But I keep getting an error saying that he only accepts one day challenges.  So I've communicated with him and suggested that he change his settings to allow longer challenges.  He says he changed those settings and all should be OK.  But I get the same error.  He now says he cannot challenge me to a 3-day game and gets an error and suggests the problem must be on my end.  But I get and give 3-day challenges all the time, so that doesn't seem like it could be the problem.

Any ideas what might be up?

Graybeard

perhaps he did change it to "Accept 3 day games" but forgot to click on the save preferences button before closing that page