On CNBC’s "Mad Money Lightning Round," Jim Cramer said American Airlines Group Inc (NASDAQ:AAL) had a good quarter. However, he believes United Airlines Holdings, Inc’s (NASDAQ:UAL) quarter was even better.

When asked about OptimizeRx Corporation (NASDAQ:OPRX), Cramer said "There’s not enough there at that company."

The "Mad Money" host said Marvell Technology, Inc. (NASDAQ:MRVL) has been going down along with some other stocks, and it’s the one that shouldn’t.

"We are looking to buy back the stock we sold," Cramer added. He also recommended not selling the stock.

When asked about ZIM Integrated Shipping Services Ltd. (NYSE:ZIM), Cramer said, when these stocks "go down, look out. And we’re in the 'look out' phase."

Cramer said he can’t own Solid Power, Inc. (NASDAQ:SLDP) as "energy storage situations are very hard."

When asked about SoFi Technologies, Inc. (NASDAQ:SOFI), he said, "Here’s the problem. This thing was built as a way to be able to help on student loans, and when you get rid of your major product." Cramer said it’s very hard to recommend this stock.

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