CRM dates one day too early when accessing them via LINQ

For one of my a clients I had to make something to import records from their old invoicing system into the new CRM via csv files. When this was completed it had to export result data they would use to check if all the data was transferred correctly. Because they had to "practice" this import many times I decided to make a Windows Forms application and access the CRM data via the API using LINQ.

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