I have a flow with a Fastlookup on the Opportunity and then a FastLookup on a custom object to pull information from the custom object and update back to the opportunity.  But the flow starting Opportunity ID is not getting pulled and i get an error that says the following:

"The record couldn’t be saved because it failed to trigger a flow. A flow trigger failed to execute the flow with version ID 301xxxxxxxxxxxx. Contact your administrator for help." 

Please help on how to get the Starting Opp ID to go through the flow in order to update that specific Opp record.
 

I have a flow with a Fastlookup on the Opportunity and then a FastLookup on a custom object to pull information from the custom object and update back to the opportunity.  But the flow starting Opportunity ID is not getting pulled and i get an error that says the following:

"The record couldn’t be saved because it failed to trigger a flow. A flow trigger failed to execute the flow with version ID 301xxxxxxxxxxxx. Contact your administrator for help." 

Please help on how to get the Starting Opp ID to go through the flow in order to update that specific Opp record.