@LauraC2 - Your client either received the EIP and forgot, or got the the EIP as a debit card and tossed it as junk mail. As mentioned earlier - don't trust the memory of your clients. https://www.irs.gov/coronavirus/economic-impact-payment-information-center can lead all you knead to knough! 

My client insisted they never got it, actually it went into their bank and they just thought it was a tax refund. Many people tossed the debits cards because the really did look like junk mail from MetaBank. (Where is MetaBank?)

Guide them through https://www.irs.gov/newsroom/questions-and-answers-about-the-first-economic-impact-payment-topic-f-p... and be sure to charge for the extra service. 

You should be able to look carefully at the Lacerte worksheet to determine if it is wrong. I really doubt it is.