HwVTEP : deleting tunnels list from physical switch is not removing the content from topology config DS

When tunnels list from physical switch is deleted using local-locator-ref and remote-locator-ref as key, it is not getting removed from topology config DS.

in hwvtep.yang, tunnels list is having a key of local and remote termination end point instance identifiers. Doubting whether yangtools is not honoring the delete.

grouping hwvtep-physical-switch-attributes {
.......

list tunnels

{ key "local-locator-ref remote-locator-ref"; uses hwvtep-tunnel-attributes ; }