Alexanderine pair infertile

[alihamza]

hi every1. i have 6 years old alexanderine pair they gave single clutch in 2023. 3 eggs 2 were early embryo death( red eggs after 35 days of incubation) and 1 was infertile. in 2024 they gave 2 clutches of 6 eggs and all were infertile..
i have seen them mating several times and female incubate eggs properly. what could be the reason? for me i think male might have some vitamin e defficiency.. need suggestions from experts.thanks