Unable to Put Call on HOLD or use Consult and Transfer

The external PSTN calls getting dropped or failing to retrieve while using the Hold or Consult and Transfer functionality seems to be a common issue, It can be resolved through different approaches such as Enabling/Disabling Refer Support on the Trunk side or Enabling/Disabling PRACK on Trunk side on SBC.
Recently one of the customers started to experience a similar issue but it was limited to one location. Therefore, Enabling/Disabling the Refer to Global Trunk configuration was not a feasible option.
Lync/SfB logs and WireShark traces reported - "Gateway responded with 491 Request Pending". It suggested the problem seems to be with SBC configuration.

On further investigation on the SBC side, it is identified that PRACK was enabled and causing the call to drop (Gateway call is not in the connected state) while using the Hold. Once the PRACK is disabled, the Hold and Consult and Transfer started to work fine.