Sparrows are primarily ground feeding birds, however they have been known to cling to a seed feeder from time to time. Also, it can take birds time to get used to a new feeder and/or food. I have attached a link to some information about this, that you may find useful.
https://www.ivelvalleybirdfood.co.uk/blog/bird-feeding/how-long-does-it-take-birds-to-eat-new-food/
