You sent some bitcoin to MultiBit Classic but the bitcoin never arrived. There is no record of the transaction in MultiBit Classic.
The first thing to check is whether the bitcoin was actually sent ok. You can do this as follows:
To get the missing transaction into your wallet:
You should then see the transaction in your wallet.
Earlier versions of MultiBit Classic did not show transactions that had inputs that were not confirmed. As this caused confusion this has been changed in version 0.5.16 so that these transactions are shown (unconfirmed). If you have an old version of MultiBit Classic download the latest copy and install it. You will need to do a 'Reset block chain and transactions' so that MultiBit Classic can resync to see any transactions like this.
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