"Hi, you must be Carol" vs "Hi, you might be Carol"

[Jctgf]

Hi, you must be Carol.

Hi, you might be Carol.

Hi,
Suppose you make and appointment with a real state broker. You both agree to meet at a certain place, at a certain hour.
When you see the lady that you presume is Carol (the real state broker), you say one of the sentences above.
Which one is the right one and why?
Thanks.

[Barb_D]

You must be Carol.

If you're really not sure, then "Excuse me. Are you Carol?"

[Molly]

Hi, you must be Carol.

More formally, in my variety at least:

Hello, might you be Carol?

NB "real estate"

[Daemon99]

The name Carol reminds me of a joke. Here it is...

Three men died on Christmas Eve and were met by Saint Peter at the Pearly Gates.

In honor of this holy season Saint Peter said, "You must each possess something that symbolizes Christmas to get into heaven."

The first man fumbled through his pockets and pulled out a lighter. He flicked it on. "It represents a candle," he said.

"You may pass through the pearly gates," Saint Peter said.

The second man reached into his pocket and pulled out a set of keys. He shook them and said, "They're bells."

Saint Peter said, "You may pass through the pearly gates."

The third man started searching desperately through his pockets and finally pulled out a pair of women's panties.

St. Peter looked at the man with a raised eyebrow and asked,

"And just what do those symbolize?"

The man replied, "These are Carol's."
_________________
Non-native speaker of English
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I intend to live forever - so far, so good.

[Lost_Soul]

That makes sense !