Powermock Whitebox with suspended functions

Trying to write unit test for private functions using WhiteBox (I know I shouldn't, but it's not my decision) Class sample:

    class Repository {
        private fun foo1(items: List<String>) { 
            println(items)
        }
        private suspend fun foo2 (items: List<String>) {
            println(items)
        }
    }

And my tests:

        val repository = = spyk(Repository(), recordPrivateCalls = true)
        @Test
        fun test1() = runBlocking { 
            Whitebox.invokeMethod<Unit>(
                repository,
                "foo1",
                listOf("")
            )
        }
        @Test
        fun test2() = runBlocking {
        Whitebox.invokeMethod<Unit>(
                repository,
                "foo2",
                listOf("")
            )
        }

test1() works, but test2 returns an error:

No method found with name 'foo2' with parameter types: [ java.util.Collections$SingletonList ]

How can I solve it?
Using Kotlin 1.3