Can you help with 'Search animals in radius' using Postman?

Hi!

I'm attempting to build a React/Node.js app that lets people search for nearby animals to rescue.

Like others I'm starting with Postman to get my API calls working properly and then will incorporate that into the app.

I can successfully pull data using most of the GET queries but am seeing this error when I try the Search Animals in Radius request:

{
"errors": {
"status": 500,
"title": "System failure",
"detail": "We experienced a system failure. Please contact support about this error if it persists."
}
}

I'm sending the (POST?) request to https://api.rescuegroups.org/v5/public/animals/search/available/cats/haspic?include=breeds,colors,fosters,locations,orgs,patterns,pictures,species,videos,videourls&fields[animals]=name,sex&fields[orgs]=name,email,url,facebookUrl,adoptionUrl&fields[breeds]=name&fields[colors]=name&fields[fosters]=name,email&fields[locations]=name&fields[patterns]=name&fields[pictures]=large,small&fields[species]=singular&fields[videos]=url&fields[videourls]=url,urlThumbnail&options=meta using my auth key in the header which I've confirmed is working on my other requests.

I'm starting super simple with my request body:

{
"data": {
"filters": 
[
],
"filterRadius":
{
"miles": 100,
"postalcode": 94301
}
}
}

Any tips? I know v5 is still not fully in production  - do I need to revert back to v2 for this kind of request and if so, am I doing this correctly in using JSON pulling 'raw' data?

Sorry for the beginner questions I was not able to find my answer in the documentation or these forums.

Thanks!

Chris