io.mockk.MockKException: no answer found for whereas any() is used as an argument

Question

Currently, I'm working on unit tests and I'm using Mockk for that purpose.

Here's how my unit test looks like (I'll put the most important lines)

@Test
fun `Test computeDowntimesOverPeriod with starting uptime`() {
   every {incidentRepository.incidentsBySiteKey(any(), any(), or(ofType(String::class), isNull()))} returns buildIncidentsStream(5)

   mockSAT123Mapping()

   val timeIntervals = incidentManager.computeDowntimesOverPeriod("SAT.123", Period.ofWeeks(1))

   //...

   verify(exactly=1) {incidentRepository.incidentsBySiteKey(Period.ofDays(7),15, "asc")}
}

Here's the signature of the incidentsBySiteKey function

fun incidentsBySiteKey(period: Period, siteId: Int?, order: String = "asc"): Stream<Incident>

For the computeDowntimesOverPeriod function

open fun computeDowntimesOverPeriod(siteKey: String, period: Period): List<StatusTimeInterval> {
   //...
   val downtimes = incidentsBySiteKeyStream(siteKey, period)
   //...
}

The incidentsBySiteKeyStream function :

private fun incidentsBySiteKeyStream(siteKey: String, period: Period, order: String = "asc"): Optional<Stream<Incident>> {
   Objects.requireNonNull(period)
   return if (StringUtils.isEmpty(siteKey)) {
      Optional.of(Stream.empty())
   } else siteMapper.fromCMMSKey(siteKey)
      .flatMap { it.toUtId() }
      .map { siteId -> incidentRepository.incidentsBySiteKey(period, siteId, order).filter { equipmentRepository.findById(it.equipmentId).get().weight > 0 } }

}

As you can see, in the computeDowntimesOverPeriod function, we use the incidentsBySiteKey function. So, in the test it's logical to check whether or not the function is called. But when I run the test, I get the following error :

io.mockk.MockKException: no answer found for: IncidentRepository(incidentRepository#28).incidentsBySiteKey(P7D, 15, asc)

So basically, my test failed when I initialized the timeIntervals variable. But why ? I mean, I have the every block that should return something for any argument.

Edit : kotlin version => 1.3.31 mockk version => 1.8.13.kotlin13