Administrative districts?

Question

JavaScript

I will briefly describe the problem.
We have a map and a filter, in the filter there are AO buttons by which objects are filtered.
There is also a user page where he can change the location of his object.
There are districts where decoding returns not what is needed.
For example, there is the ZelAO district.
If you make a decoded request to any address of this district, then the answer is not the name of the district, but the city of Zelenograd. You can use the OSM map API, the county is returned as expected. But this is an extra request for an external resource. It is possible to determine the AO by an array of coordinates, but I would like to refuse this, since it will cause a load.
The question is next.
How else can you define AO ​​through decoding, without multipolygons and unnecessary requests for external resources?