How to convert Swift Date or String to timestamp without time zone of PostgreSQL?

I am using Vapor 3, Swift 5.1, PostgreSQL 12, and Postico 1.5.10 for my Backend. In the PostgreSQL database, there is a field with the name eventDate of type timestamp without time zone. Please, look at screenshot:

In Vapor, there is a model:

import Vapor
import FluentPostgreSQL

final class TestModel: PostgreSQLModel {

    var id: Int?
    var eventDate: Date

    init(eventDate: Date) {
        self.eventDate = eventDate
    }

}

extension TestModel: Content {
}

extension TestModel: Migration {
}

extension TestModel: Parameter {
}

But when I am trying to save Date (Swift) to timestamp without time zone Vapor gives me error:

[ ERROR ] DecodingError.typeMismatch: Value of type 'String' required for key 'eventDate.date'. (NIOServer.swift:104)

If, in model, I am changing Date to String, Vapor gives me this error:

[ ERROR ] PostgreSQLError.server.error.transformAssignedExpr: column "eventDate" is of type timestamp without time zone but expression is of type text (NIOServer.swift:104)

So the question is: how to transfer Date and String to timestamp without time zone (or timestamp with time zone)?

I will be thankful for any help or advice!

It's no 100% solution I wanted but it's also very good.

import Vapor
import FluentPostgreSQL

final class TestModel: PostgreSQLModel {

    static var createdAtKey: TimestampKey? = \.createdAt

    var id: Int?
    var someValue: Int
    var someOtherProprty: String
    var createdAt: Date?

    init(someValue: Int, someOtherProprty: String) {
        self.someValue = someValue
        self.someOtherProprty = someOtherProprty
    }

}

extension TestModel: Content {
}

extension TestModel: Migration {
}

extension TestModel: Parameter {
}