This is know as erectile dysfunction there are many reason for this  is ur age it impacts badly 1) Anexity/ stress or tention 2)Are u on any medication any infection or trauma 3) Do ur blood test for testosterone free and total to know ur exact status 4) we can treat it with ayurvedic medicine to improve ur erection so that u can have sex without any side effect it will cure completely but will take time 5) Need to council ur wife as this is very very important

at 46 yrs age, Erection issues means.... rule out diabetes, thyroid problems and sex hormones drop etc. For that you better contact sexologist nearby.