software bug ?

all of the sudden I had problems with my g4 running marshmallow
most google apps stopped working (gmail - google store - google keep etc ...)
and some apps stopped opening ( 365scores etc ...... )
so i did factory reset
it worked well for 24 hours then i faced the same problem again
i did factory reset again and it worked for only about 24 hours too
note : it is not rooted
anybody have a solution ?

thanks in advance