[Home](./index.md) > [sip.js](./sip.js.md) > [RequestPendingError](./sip.js.requestpendingerror.md) ## RequestPendingError class An exception indicating an outstanding prior request prevented execution. Signature: ```typescript export declare class RequestPendingError extends Exception ``` ## Remarks The constructor for this class is marked as internal. Third-party code should not call the constructor directly or create subclasses that extend the `RequestPendingError` class.