There's only one NT advertisement for your U21 saved and that one has the salary limit set to 3500 for 18 year old's (it's the old message). However, I see that the senior NT coach has set the right message. Since the U21 message is still functional, it is overriding the senior ad. So, please update your U21 ad (set those salary limits to some very high numbers) and there should be no problem.