Dynamics CRM Online Qualify Lead = Business Process Error

<s:Envelope xmlns:s="schemas.xmlsoap.org/.../envelope"><s:Body><s:Fault><faultcode>s:Client</faultcode><faultstring xml:lang="en-US">Object reference not set to an instance of an object.</faultstring><detail><OrganizationServiceFault xmlns="schemas.microsoft.com/.../Contracts" xmlns:i="www.w3.org/.../XMLSchema-instance"><ErrorCode>-2147220891</ErrorCode><ErrorDetails xmlns:a="schemas.datacontract.org/.../System.Collections.Generic"><KeyValuePairOfstringanyType><a:key>OperationStatus</a:key><a:value i:type="b:int" xmlns:b="www.w3.org/.../XMLSchema">0</a:value></KeyValuePairOfstringanyType><KeyValuePairOfstringanyType><a:key>SubErrorCode</a:key><a:value i:type="b:int" xmlns:b="www.w3.org/.../XMLSchema">-2146233088</a:value></KeyValuePairOfstringanyType></ErrorDetails><Message>Object reference not set to an instance of an object.</Message><Timestamp>2017-02-13T17:02:13.4316838Z</Timestamp><ExceptionSource>PluginExecution</ExceptionSource><InnerFault i:nil="true"/><OriginalException>Microsoft.Xrm.Sdk.InvalidPluginExecutionException
   at G2.CRM.Plugin.Opportunity.Execute(IServiceProvider serviceProvider)
   at Microsoft.Crm.Sandbox.SandboxAppDomainHelper.&lt;&gt;c__DisplayClass7.&lt;Execute&gt;b__0()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at Microsoft.Crm.Sandbox.SandboxAppDomainHelper.Execute(IOrganizationServiceFactory organizationServiceFactory, Dictionary`2 sandboxServices, String pluginTypeName, String pluginConfiguration, String pluginSecureConfig, IPluginExecutionContext requestContext)
   at Microsoft.Crm.Sandbox.SandboxAppDomainHelper.Execute(IOrganizationServiceFactory organizationServiceFactory, Dictionary`2 sandboxServices, String pluginTypeName, String pluginConfiguration, String pluginSecureConfig, IPluginExecutionContext requestContext)
   at Microsoft.Crm.Sandbox.SandboxWorker.Execute(SandboxCallInfo callInfo, SandboxPluginExecutionContext requestContext, Guid pluginAssemblyId, Int32 sourceHash, String assemblyName, Guid pluginTypeId, String pluginTypeName, String pluginConfiguration, String pluginSecureConfig, SandboxRequestCounter&amp; workerCounter, Boolean returnTraceInfo)</OriginalException><TraceText>
[G2.CRM.Plugin: G2.CRM.Plugin.Opportunity]
[e7ac5689-20e4-e611-80fe-5065f38a4b71: G2.CRM.Plugin.Opportunity: Update of opportunity]</TraceText></OrganizationServiceFault></detail></s:Fault></s:Body></s:Envelope>