I send some coins to an exchange and I have this message in the transactions:
Status: 0/unconfirmed
Date: 29/01/2018 07:17
To: Stocks hQbXjhzYXfZjHja1sLTQPjBiJRXD71iFrG
Debit: -2.02218068 BHD
Transaction fee: -0.0001 BHD
Net amount: -2.02228068 BHD
Transaction ID: 272667f922648950a489b44993aec77f1af93fd91ca94f591a0d2981bbca627b-000
I never received my coins and they are not available in my wallet anymore

Impossible to find the transaction in the block explorer.
Help please

There is no such transaction. So all coins in your wallet.
Type repairwallet in Console and restart the wallet.