授权第三方的时候返回这个报错，请求各位帮忙解答一下，谢谢。

"Exception has been thrown by the target of an invocation.；ex:System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.IO.FileNotFoundException: Could not load file or assembly 'Senparc.Weixin.MP, Version=13.4.1.29597, Culture=neutral, PublicKeyToken=null' or one of its dependencies. The system cannot find the file specified.

at XYHis.Service.InterfaceService.WeChatServices.GetWeChatCode()

--- End of inner exception stack trace ---

at System.RuntimeMethodHandle.InvokeMethod(Object target, Object[] arguments, Signature sig, Boolean constructor)

at System.Reflection.RuntimeMethodInfo.UnsafeInvokeInternal(Object obj, Object[] parameters, Object[] arguments)

at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)

at System.Reflection.MethodBase.Invoke(Object obj, Object[] parameters)

at XYHis.ApiServiceWeb.Controllers.ControllerFactory.DoMethod(String assemblyName, String className, String methodName)

at XYHis.ApiServiceWeb.Controllers.WechatController.PostCallInterface()"