How can the present two popes and the Synods use a false premise to change the understanding of the Nicene Creed, reject the Athanasius Creed, interpret Vatican Council II irrationally- and they reject mortal sin with their approval of Amoris Laetitia - and then offer Holy Mass ?

 How can the present two popes and the Synods use a false premise to  change the understanding of the Nicene Creed, reject the Athanasius Creed, interpret Vatican Council II irrationally-  and they reject mortal sin with their approval of Amoris Laetitia - and then offer Holy Mass ? - Lionel  Andrades