At my place there was a playground field, but unfortunately there is no more playground there, it’s was vandalism and already remove from there now it’s was a empty ground…in that case I can’t nominate for PokeStop..what to do for that…
Welcome to the forum!
So you want to submit the field as a place to play in itself? That is a difficult nomination, but you could still submit it as a park area, if that is what it is.
If you would like to share the location, we might be able to give better advice. But remember that this is a public forum and don’t divulge personal information.
If it’s sometimes used with portable sports equipment, such as practice sized soccer goals, I would take pictures with them present.