J.K.Yajnik - Karan Park, Astron Socity, Shree Colony, Parnkuti Society, Amin Road.. Karan Park Rajkot Gujarat

I do observe a couple that is male and female mostly everyday in and around my residence and I have put up
nest in my house but somehow sparrows are not visiting my
house nowadays. Previously one cople (male and female)
visited my back yard and front compound for a week or so
and also tried the nest by sitting inside it.
But after their frequent visit of the nest for two-three daysto they somehow stopped visiting even my house.
Please give me your suggestions for attracting the sparrows to build the nest or reside in the nest that i have fixed
for them.
Further, also tell me where can i get the nest that is marketed by Hirval Foundation.