Not able to modify Recurring Transactions for contacts with multiple subscriptions, whether active or inactive

When I try update a recurring subscription through Civi for someone with multiple recurring subscriptions, even if there is only one active recurring subscription, I get the endlessly spinning Civi icon and the following message in the log :

[error] $Fatal Error Details = array:3 [ "message" => "Expected one ContributionRecur but found 25" "code" => null "exception" => CiviCRM_API3_Exception {#2161 -extraParams: array:4 [ "count" => 25 "is_error" => 1 "error_message" => "Expected one ContributionRecur but found 25" "error_code" => "undefined" ] #message: "Expected one ContributionRecur but found 25" #code: 0 #file: ".../sites/all/modules/civicrm/api/api.php" #line: 133 trace: { .../sites/all/modules/civicrm/api/api.php:133 { › if (is_array($result) && !empty($result['is_error'])) { › throw new CiviCRM_API3_Exception($result['error_message'], CRM_Utils_Array::value('error_code', $result, 'undefined'), $result); › } } .../sites/default/files/civicrm/extensions/authnet-master/CRM/Core/Payment/AuthorizeNetCommon.php:578 { …} .../sites/all/modules/civicrm/CRM/Contribute/Form/UpdateSubscription.php:212 { …} .../sites/all/modules/civicrm/CRM/Core/Form.php:526 { …} .../sites/all/modules/civicrm/CRM/Core/StateMachine.php:144 { …} .../sites/all/modules/civicrm/CRM/Core/QuickForm/Action/Next.php:43 { …} .../sites/all/modules/civicrm/packages/HTML/QuickForm/Controller.php:203 { …} .../sites/all/modules/civicrm/packages/HTML/QuickForm/Page.php:103 { …} .../sites/all/modules/civicrm/CRM/Core/Controller.php:347 { …} .../sites/all/modules/civicrm/CRM/Utils/Wrapper.php:98 { …} .../sites/all/modules/civicrm/CRM/Core/Invoke.php:286 { …} .../sites/all/modules/civicrm/CRM/Core/Invoke.php:69 { …} .../sites/all/modules/civicrm/CRM/Core/Invoke.php:36 { …} .../sites/all/modules/civicrm/drupal/civicrm.module:458 { …} .../includes/menu.inc:527 { …} .../index.php:21 { …} } } ]

Interesting that there are more than 25 recurring subscriptions on this account ("but found 25") however there are 25 with a value in the Installments field. (this is the contact record we use to test) Is there something in the code that is looking for recurrings with something in that field?