public async Task GetAccountAsync_WithAccountIbanExists_ReturnAccountResponse()
        {
            // Arrange
            var accountIban = "AAAAA";

            var account = new Account
            {
                AccountIban = "AAAAA",
                Balance     = 1000
            };

            accountRepository
            .GetByAccountIbanAsync(Arg.Any <string>())
            .Returns(Task.FromResult(account));

            // Act
            var accountResponse = await customerAccountsService.GetAccountAsync(accountIban);

            // Assert
            Assert.NotNull(accountResponse);
            Assert.Equal(accountIban, accountResponse.AccountIban);
            Assert.Equal(1000, accountResponse.Balance);
        }