Define a default operator class for DateTimeRangeField index

Hi
I build this model which has two DateTimeRange fields:

class Booking(BaseModel):

class Status(models.TextChoices):
    PAID = "Paid", _("Paid")
    EXPIRED = "Expired", _("Expired")
    PEDNING = "Pending", _("Pending")
    ACCEPTED = "Accepted", _("Accepted")
    REJECTED = "Rejected", _("Rejected")
    CANCELLED = "Cancelled", _("Cancelled")

related_property = models.ForeignKey(
    to='Property.Property', on_delete=models.PROTECT, null=False,
    verbose_name=_("Property"), related_name="bookings", related_query_name="booking"
    )
client = models.ForeignKey(
    to='Authentication.Client', on_delete=models.PROTECT, null=False,
    verbose_name=_("User"), related_name="reservations", related_query_name="reservation"
)
client_checking_range = DateTimeRangeField(
    default_bounds='[]', verbose_name=_("Reservation"), null=True) # to be false
original_reservation = DateTimeRangeField(
    default_bounds='[]', verbose_name=_('Original Reservation'), null=True) # to be false
checked_in = models.BooleanField(default=False, null=False, verbose_name=_('Checked In'))
checked_out = models.BooleanField(default=False, null=False, verbose_name=_('Checked Out'))
price = models.PositiveIntegerField(verbose_name=_("Price"), null=False, default=1) # default to be removed
num_of_adults = models.SmallIntegerField(null=False, verbose_name=_("Num of adults"))
num_of_children = models.SmallIntegerField(null=False, verbose_name=_("Num of children"))
status = models.CharField(verbose_name=_("Status"), max_length=16,
    choices=Status.choices, default=Status.PEDNING, null=False)

class Meta:
    verbose_name = _("Booking")
    verbose_name_plural = _("Bookings")

    indexes = [
        # models.Index(fields=['client_checking_range',]),
        GinIndex(
            fields=['client_checking_range', ],
            name='booking_client_range_gin_idx'
        )
        # GistIndex(
        #     fields=('client_checking_range',),
        #     name='checking_range_gist_idx',
        #     buffering=True
        #     ),
        # GistIndex(
        #     OpClass('client_checking_range', name='range_ops'),
        #     # fields=('client_checking_range', ),
        #     name='client_checking_range_gist_idx',
        #     # opclasses=['range_ops'],
        #     buffering=True
        #     ),
        # GistIndex(
        #     fields=('original_reservation', ),
        #     name='original_reservation_gist_idx',
        #     opclasses=['range_ops'],
        #     buffering=True
        #     )
    ]

    constraints = [
        ExclusionConstraint(
            name="non_overlapped_reservation",
            expressions=[
                # ("client_checking_range", RangeOperators.OVERLAPS),
                (OpClass("client_checking_range", name="range_ops"), RangeOperators.OVERLAPS),
                ("related_property", RangeOperators.EQUAL)
            ],
            condition=Q(status="Accepted") | Q(status="Paid") | Q(status="Pending"),
        )
    ]

I built the rest api for this model and do some tests on postman, then I try to build unittest for this APIs, and when I call pytest from the terminal, it always show this error message:
E django.db.utils.ProgrammingError: data type bigint has no default operator class for access method “gist”
E HINT: You must specify an operator class for the index or define a default operator class for the data type.

as you can see in the model I try multiple indexing solutions (and others tried but not showed here) but the result still same, so any one can help me with this problem?

thanks very much