REST API Add CoPersonRoles causes Notice with stack trace

A POST to add a new CoPersonRole object works and properly returns a 201 but it does cause this to be logged:

comanage_comanage-registry.1.36h5rlagsvki@parsley | 2022-02-18 14:09:47 Notice: Notice (8): Undefined index: in [/srv/comanage-registry/app/Model/CoPerson.php, line 900]
comanage_comanage-registry.1.36h5rlagsvki@parsley | Trace:
comanage_comanage-registry.1.36h5rlagsvki@parsley | ErrorHandler::handleError() - CORE/Cake/Error/ErrorHandler.php, line 230
comanage_comanage-registry.1.36h5rlagsvki@parsley | CoPerson::recalculateStatus() - APP/Model/CoPerson.php, line 900
comanage_comanage-registry.1.36h5rlagsvki@parsley | CoPersonRole::afterSave() - APP/Model/CoPersonRole.php, line 283
comanage_comanage-registry.1.36h5rlagsvki@parsley | CakeEventManager::dispatch() - CORE/Cake/Event/CakeEventManager.php, line 242
comanage_comanage-registry.1.36h5rlagsvki@parsley | Model::_doSave() - CORE/Cake/Model/Model.php, line 1970
comanage_comanage-registry.1.36h5rlagsvki@parsley | Model::save() - CORE/Cake/Model/Model.php, line 1754
comanage_comanage-registry.1.36h5rlagsvki@parsley | Model::saveAssociated() - CORE/Cake/Model/Model.php, line 2515
comanage_comanage-registry.1.36h5rlagsvki@parsley | Model::saveAll() - CORE/Cake/Model/Model.php, line 2287
comanage_comanage-registry.1.36h5rlagsvki@parsley | StandardController::add() - APP/Controller/StandardController.php, line 141
comanage_comanage-registry.1.36h5rlagsvki@parsley | CoPersonRolesController::add() - APP/Controller/CoPersonRolesController.php, line 94
comanage_comanage-registry.1.36h5rlagsvki@parsley | ReflectionMethod::invokeArgs() - [internal], line ??
comanage_comanage-registry.1.36h5rlagsvki@parsley | Controller::invokeAction() - CORE/Cake/Controller/Controller.php, line 499
comanage_comanage-registry.1.36h5rlagsvki@parsley | Dispatcher::_invoke() - CORE/Cake/Routing/Dispatcher.php, line 193
comanage_comanage-registry.1.36h5rlagsvki@parsley | Dispatcher::dispatch() - CORE/Cake/Routing/Dispatcher.php, line 167
comanage_comanage-registry.1.36h5rlagsvki@parsley | [main] - APP/webroot/index.php, line 96