Ive just changed Broadband provider from Sky to Vodafone (UK)

I swapped everthing over from the Sky router to  the Vodafone router (TGH3000) and the EAP225 wifi wouldnt  work and kept getting "Incorrect Password" Message  when tring to select wifi with iphone or ipad and just not connecting with various laptops/TV 's etc

I spent all day yesterday and part of this morning on it and found this out

When I have all the AP's with only 2.4g enabled with Full security password + 5g disabled all works fine

When I have all the AP's with only 2.4g enabled and Full security password and 5g enabled with No security password it all works fine

So it only  fails when the 5g is enabled with security password enabled

Any ideas ???

My set up worked ok With the sky router and with the Virgin router prevoius to that .

I could possible live with only 2.4g but not sure I should have too !,so may have to go back to sky / virgin

thanks