Here you are using Lookup Cascading Pattern. Please make sure the following:

1. First Lookup -- Setup the cache property to FULL Cache. This will have 2 outputs for you. 1 All exact match records and second rejected records.

All Exact match records direct them to UNION ALL task.

2. For Rejected records in Setp1 -- map it to second look up and set its properties to partial Cache.

All matches redirect them to UNION All Task.

3. Rejected records in Step 2 -- Map it to NO Cache lookup

All matches redirect them to UNION All task

Rejected records created a surrogate key in the lookup and then update the record and redirect output to UNION all.

It would be nice if you could give a image of your current SSIS package for further inputs.