As a reminder, rate plans are not controlled by myallocator but are instead setup and controlled directly through your channel extranets. More information about this process can be found here:
For most channels, you can control the rate plans directly in the channel extranet, including closing the ones you want to close.
For assistance with that process, you must contact your channel (OTA) account manager.
Please note: do not contact customer service in the case of booking.com or Expedia, as only your Account/Market Manager can assist you with rate plans.