ThreadPoolExecution error with scala, slick, specs2 - scala

Question

I am trying to write a db unit test for my module using slick and specs2 in scala language. I have written two tests at the moment but the second one fails with ThreadPoolExecution error.
I have tried many approaches but still can't manage to solve my problem.
Any help would be greatly appreciated.
Here is the test code:
class UserClientSpecs extends Specification{
"App should " should {
"add value to database" in new WithApplication {
println("before first test")
val recordEntry = new UserClient(None, "Lohs_atkal", 2)
val newRecord = UserService.addUser(recordEntry)
newRecord.onComplete {
case Success(value) => println(s"Got the callback, meaning = $value")
case Failure(e) => println(e.getMessage)
}
newRecord should not beNull
val count = UserService.listAllUsers.map {
v =>
println("the number of database entries are " + v.length)
}
}
"delete a record" in new WithApplication {
println("before second test")
val recordEntry = new UserClient(Some(0), "Lielaks Lohs", 5)
val newRecord = UserService.addUser(recordEntry)
newRecord.map {
v => println("newRecord value", v)
}
newRecord.onComplete {
case Success(value) => println(s"Got the callback, meaning = $value")
case Failure(e) => println(e.getMessage)
}
val recordEntry2 = new UserClient(Some(1), "Lielaks Lohs2", 50)
val newRecord2 = UserService.addUser(recordEntry2)
val countOne = UserService.listAllUsers.map {
res =>
println(res.length)
}
val deleteUser = UserService.deleteUser(1)
val countTwo = UserService.listAllUsers.map {
res =>
res should_==(1)
res should !==(2)
}
}
}
}
And the error I am getting when running my test through sbt -> testOnly:
[play-scala] $ testOnly models.UserClientSpecs
[info] UserClientSpecs
[info]
before first test
Got the callback, meaning = Some(UserClient(None,Lohs_atkal,2))
the number of database entries are 1
[info] App should should
[info] + add value to database
before second test
Task slick.backend.DatabaseComponent$DatabaseDef$$anon$2#6d01394 rejected from java.util.concurrent.ThreadPoolExecutor#7fa5be9b[Terminated, pool size = 0, active threads = 0, queued tasks = 0, completed tasks = 2]
[info] + delete a record
[info]
[info] Total for specification UserClientSpecs
[info] Finished in 2 seconds, 739 ms
[info] 2 examples, 0 failure, 0 error
[info]
[info] Passed: Total 2, Failed 0, Errors 0, Passed 2
[success] Total time: 8 s, completed Mar 10, 2016 1:40:10 PM