apm-agent-dotnet: Null pointer in PayloadSenderV2

Having that error on remote server, but can not reproduce on local

Aug  3 01:22:24 server1 integration[4834]: [2019-08-02 11:22:24][Debug] - {Tracer} Starting Transaction{Id: 8525f9f45ad1798f, TraceId: 1b20305c5f76358cb3424438c407522f, ParentId: null, Name: POST /api/xx/deposit, Type: request, IsSampled: True}

Then there is a bunch of spans from entity framework

And last lines are :

Aug  3 01:22:26 server1 integration[4834]: [2019-08-02 11:22:26][Debug] - {PayloadSenderV2} Transaction added to the queue, Transaction{Id: 8525f9f45ad1798f, TraceId: 1b20305c5f76358cb3424438c407522f, ParentId: null, Name: POST Xx/Deposit, Type: request, IsSampled: True}
Aug  3 01:22:26 server1 integration[4834]: [2019-08-02 11:22:26][Debug] - {Transaction} Ending Transaction{Id: 8525f9f45ad1798f, TraceId: 1b20305c5f76358cb3424438c407522f, ParentId: null, Name: POST Xx/Deposit, Type: request, IsSampled: True}
Aug  3 01:22:26 server1 integration[4834]: [2019-08-02 11:22:26][Warning] - {PayloadSenderV2} Failed sending events. Following events were not transferred successfully to the server:
Aug  3 01:22:26 server1 integration[4834]: Span{Id: 8bb96752463c20a8, TransactionId: 8525f9f45ad1798f, ParentId: 8525f9f45ad1798f, TraceId: 1b20305c5f76358cb3424438c407522f, Name: SELECT x.id, x.extra, x.game_id, x."order", x.partner_aggregator_id, x.product_type, x.status, "x.Game".id, "x.Game".device_type, "x.Game".external_id, "x.Game".extra, "x.Game".has_demo, "x.Game".image_url, "x.Game".provider_id, "x.Game".recalled_at, "x.Game".released_at, "x.Game".status, "x.Game".token
Aug  3 01:22:26 server1 integration[4834]: FROM common.partner_games_new AS x
Aug  3 01:22:26 server1 integration[4834]: INNER JOIN common.partner_aggregators AS "x.PartnerAggregator" ON x.partner_aggregator_id = "x.PartnerAggregator".id
Aug  3 01:22:26 server1 integration[4834]: INNER JOIN common.games AS "x.Game" ON x.game_id = "x.Game".id
Aug  3 01:22:26 server1 integration[4834]: WHERE (("x.Game".external_id = @__gameExtId_0) AND EXISTS (
Aug  3 01:22:26 server1 integration[4834]:     SELECT 1
Aug  3 01:22:26 server1 integration[4834]:     FROM common.aggregator_games AS y
Aug  3 01:22:26 server1 integration[4834]:     INNER JOIN common.aggregators AS "y.Aggregator" ON y.aggregator_id = "y.Aggregator".id
Aug  3 01:22:26 server1 integration[4834]:     WHERE "y.Aggregator".type IN (9) AND ("x.Game".id = y.game_id))) AND "x.PartnerAggregator".partner_id IN (4)
Aug  3 01:22:26 server1 integration[4834]: LIMIT 1, Type: db, IsSampled: True},
Aug  3 01:22:26 server1 integration[4834]: Span{Id: 9c0999c76d9d3327, TransactionId: 8525f9f45ad1798f, ParentId: 8525f9f45ad1798f, TraceId: 1b20305c5f76358cb3424438c407522f, Name: UPDATE xx.rounds SET is_finished = @p0
Aug  3 01:22:26 server1 integration[4834]: WHERE id = @p1;
Aug  3 01:22:26 server1 integration[4834]: INSERT INTO xx.transactions (amount, client_id, created_at, currency, external_id, game_external_id, partner_game_id, round_id, status, token, type)
Aug  3 01:22:26 server1 integration[4834]: VALUES (@p2, @p3, @p4, @p5, @p6, @p7, @p8, @p9, @p10, @p11, @p12)
Aug  3 01:22:26 server1 integration[4834]: RETURNING id;
Aug  3 01:22:26 server1 integration[4834]: , Type: db, IsSampled: True},
Aug  3 01:22:26 server1 integration[4834]: Transaction{Id: 8525f9f45ad1798f, TraceId: 1b20305c5f76358cb3424438c407522f, ParentId: null, Name: POST Xx/Deposit, Type: request, IsSampled: True}
Aug  3 01:22:26 server1 integration[4834]: Exception: System.NullReferenceException, Message: Object reference not set to an instance of an object.

Any ideas about Exception: System.NullReferenceException, Message: Object reference not set to an instance of an object. ?