@Rainer_Leon This must be Atlas bug, I can reproduce the problem, when I insert from Atlas Web UI, it inserts it as
{
"_id" : ObjectId("5e56fc89f1f42d119bca2302"),
"provider_id" : BinData(3, "ceYVP/wDRxCwZXhlMwNaQQ==")
}
When I insert same thing from Studio 3T or Compass I get this
{
"_id" : ObjectId("5e56fe213a3725650e75c144"),
"provider_id" : {
"$binary" : {
"base64" : "EEcD/D8V5nFBWgMzZXhlsA==",
"subType" : "04"
}
}
}