i am using htable to assign internal transaction index and label.however its unable to assign the index and label

modparam("htable", "htable", "hte=>size=8;autoexpire=300")

$sht(hte=>id_index::$rU) = $T(id_index)

$sht(hte=>id_label::$rU) = $T(id_label);

Logs:-

<script>: proceesing suspended in trasaction [10701:2082699975]
Sep 28 04:44:19 ip-172-31-36-96 /usr/sbin/kamailio[98519]: ERROR: {1 29982 INVITE 8f62773bc3dc44a9adb32723f0d0e269} <core> [core/lvalue.c:353]: lval_pvar_assign(): setting pvar failed
Sep 28 04:44:19 ip-172-31-36-96 /usr/sbin/kamailio[98519]: ERROR: {1 29982 INVITE 8f62773bc3dc44a9adb32723f0d0e269} <core> [core/lvalue.c:404]: lval_assign(): assignment failed at pos: (570,32-570,43)
Sep 28 04:44:19 ip-172-31-36-96 /usr/sbin/kamailio[98519]: ERROR: {1 29982 INVITE 8f62773bc3dc44a9adb32723f0d0e269} <core> [core/lvalue.c:353]: lval_pvar_assign(): setting pvar failed
Sep 28 04:44:19 ip-172-31-36-96 /usr/sbin/kamailio[98519]: ERROR: {1 29982 INVITE 8f62773bc3dc44a9adb32723f0d0e269} <core> [core/lvalue.c:404]: lval_assign(): assignment failed at pos: (571,32-571,43)
Sep 28 04:44:19 ip-172-31-36-96 /usr/sbin/kamailio[98519]: INFO: {1 29982 INVITE 8f62773bc3dc44a9adb32723f0d0e269} <script>: [SUSPEND] htable key value [<null>   --   <null>]

Is there any solution for this issue?

Thanks,

Uttam