Just now, I got a HTTP 500 error code again:
{
"log": {
"version": "1.2",
"creator": {
"name": "Firefox",
"version": "94.0"
},
"browser": {
"name": "Firefox",
"version": "94.0"
},
"pages": [
{
"startedDateTime": "2023-09-05T13:06:52.523+02:00",
"id": "page_1",
"title": "Mapillary",
"pageTimings": {
"onContentLoad": -3695860,
"onLoad": -3689077
}
}
],
"entries": [
{
"pageref": "page_1",
"startedDateTime": "2023-09-05T13:06:53.958+02:00",
"request": {
"bodySize": 0,
"method": "GET",
"url": "https://graph.mapillary.com/location_search?query=9%20olimpi&access_token=MLY|4223665974375089|d62822dd792b6a823d0794ef26450398&locale=en_US",
"httpVersion": "HTTP/1.1",
"headers": [
{
"name": "Host",
"value": "graph.mapillary.com"
},
{
"name": "User-Agent",
"value": "Mozilla/5.0 (X11; Linux x86_64; rv:94.0) Gecko/20100101 Firefox/94.0"
},
{
"name": "Accept",
"value": "application/json, text/plain, */*"
},
{
"name": "Accept-Encoding",
"value": "gzip, deflate, br"
},
{
"name": "Origin",
"value": "https://www.mapillary.com"
},
{
"name": "Connection",
"value": "keep-alive"
},
{
"name": "Sec-Fetch-Dest",
"value": "empty"
},
{
"name": "Sec-Fetch-Mode",
"value": "cors"
},
{
"name": "Sec-Fetch-Site",
"value": "same-site"
}
],
"cookies": [],
"queryString": [
{
"name": "query",
"value": "9 olimpi"
},
{
"name": "access_token",
"value": "MLY|4223665974375089|d62822dd792b6a823d0794ef26450398"
},
{
"name": "locale",
"value": "en_US"
}
],
"headersSize": 457
},
"response": {
"status": 500,
"statusText": "Internal Server Error",
"httpVersion": "HTTP/1.1",
"headers": [
{
"name": "Content-Encoding",
"value": "br"
},
{
"name": "Vary",
"value": "Origin"
},
{
"name": "Vary",
"value": "Accept-Encoding"
},
{
"name": "x-app-usage",
"value": "{\"call_volume\":0,\"cpu_time\":0}"
},
{
"name": "Content-Type",
"value": "application/json; charset=UTF-8"
},
{
"name": "WWW-Authenticate",
"value": "OAuth \"Facebook Platform\" \"unknown_error\" \"An unexpected error has occurred. Please retry your request later.\""
},
{
"name": "mapillary-api-version",
"value": "v1.0"
},
{
"name": "Access-Control-Allow-Origin",
"value": "*"
},
{
"name": "Strict-Transport-Security",
"value": "max-age=31536000; preload; includeSubDomains"
},
{
"name": "Pragma",
"value": "no-cache"
},
{
"name": "Cache-Control",
"value": "no-store"
},
{
"name": "Expires",
"value": "Sat, 01 Jan 2000 00:00:00 GMT"
},
{
"name": "x-fb-request-id",
"value": "A8qqL8kcwnavP2AiRLXEHwV"
},
{
"name": "x-fb-trace-id",
"value": "HYiAuNB5Pxg"
},
{
"name": "x-fb-rev",
"value": "1008438023"
},
{
"name": "X-FB-Debug",
"value": "7WutPiCLn/cuB+7BbZ/GauccVymhdUfvSEQ+pyCJ3h+bBgKeTA0b77zeLozN26lIJJy9gfxBXyAih+6XJ5zfcg=="
},
{
"name": "Date",
"value": "Tue, 05 Sep 2023 11:06:56 GMT"
},
{
"name": "Alt-Svc",
"value": "h3=\":443\"; ma=86400"
},
{
"name": "Connection",
"value": "keep-alive"
},
{
"name": "Content-Length",
"value": "169"
}
],
"cookies": [],
"content": {
"mimeType": "application/json; charset=UTF-8",
"size": 232,
"text": "{\n \"error\": {\n \"message\": \"An unexpected error has occurred. Please retry your request later.\",\n \"type\": \"OAuthException\",\n \"is_transient\": true,\n \"code\": 2,\n \"fbtrace_id\": \"A8qqL8kcwnavP2AiRLXEHwV\"\n }\n}"
},
"redirectURL": "",
"headersSize": 836,
"bodySize": 1005
},
"cache": {},
"timings": {
"blocked": 66,
"dns": 0,
"connect": 22,
"ssl": 34,
"send": 0,
"wait": 2507,
"receive": 0
},
"time": 2629,
"_securityState": "secure",
"serverIPAddress": "157.240.27.18",
"connection": "443"
}
]
}
}
system SERVER ERROR: 500 Internal Server Error Object { error: {…} } main.ea19a26694fd7fa2.js:1:551355
I cannot seem to replicate this today but on Sunday it happened with every query. Lately, the search now and then ceases to work either but without a HTTP 500 error code. 
I am unable to make out any other trigger than request timing. Try to throttle and increase latency when testing. Make sure you test the complete website not just the search separately.