Copy Data Function droppping records

Question

I have set up a copy data pipeline in Azure Datafactory. The table I'm copying from contains 1500 records. The copy data step only read 872 records. I've tried to find records in the input table that seem to have bad data but nothing seems to be excessive long text or the wrong data type. I also looked for duplicate keys but I don't find any fields in the input record layout that indicate they are a key. Does anyone have suggestions as to what I should look for or try to change to resolve the issue?