how to store stringify json data into mongodb using C# MongoDB.Driver

Question

i am fetching data in strigify json format

"[{\"ApplytoAllYesNo\":\"\",\"PartNumber\":\"\",\"Description\":\"\",\"LotNumber\":\"\",\"Revision\":\"\",\"Comment\":\"\",\"QualStatus\":\"\",\"Upload\":\"\",\"buildID\":\"62161d4fee3776fba3d8b83e\"},{\"ApplytoAllYesNo\":\"\",\"PartNumber\":\"\",\"Description\":\"\",\"LotNumber\":\"\",\"Revision\":\"\",\"Comment\":\"\",\"QualStatus\":\"\",\"Upload\":\"\",\"buildID\":\"62161d4fee3776fba3d8b83e\"},{\"ApplytoAllYesNo\":\"\",\"PartNumber\":\"\",\"Description\":\"\",\"LotNumber\":\"\",\"Revision\":\"\",\"Comment\":\"\",\"QualStatus\":\"\",\"Upload\":\"\",\"buildID\":\"62161d4fee3776fba3d8b83e\"},{\"ApplytoAllYesNo\":\"\",\"PartNumber\":\"\",\"Description\":\"\",\"LotNumber\":\"\",\"Revision\":\"\",\"Comment\":\"\",\"QualStatus\":\"\",\"Upload\":\"\",\"buildID\":\"62161d4fee3776fba3d8b83e\"},{\"ApplytoAllYesNo\":\"\",\"PartNumber\":\"\",\"Description\":\"\",\"LotNumber\":\"\",\"Revision\":\"\",\"Comment\":\"\",\"QualStatus\":\"\",\"Upload\":\"\",\"buildID\":\"62161d4fee3776fba3d8b83e\"}]"

every time this data will change, that's why I am unable to use fixed model hear as my object won't have fixed number of columns, and number columns will change in each request, these columns created in front end.

I just want to insert json strigify data into mongoDB whatever it comes in that object.

[HttpPost("saveBuildData")]
    public async void saveBuildData(BuildSchema data)
    {            
        await _buildsService.insertBuildConfigData(data.buildData);            
    }

public async Task insertBuildConfigData(dynamic obj)
    {
        var connectionString = _configuration["DatabaseSettings:ConnectionString"];
        var client = new MongoClient(connectionString);
        var database = client.GetDatabase("cascade");
        var collection = database.GetCollection<BsonDocument>("buildconfig_MATERIAL");
        var q = BsonSerializer.Deserialize<BsonDocument>(obj);
        await collection.InsertOneAsync(q);
    }

above code is not working and I am unable to insert the data into mongoDB.

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