There are several reasons why your bank doesn`t let you cash the check.
Here are some of the reasons:
Maybe the name of your check is not the same with your valid ID`s like driver`s license,
or the check is a crossed-check.
Once the check is crossed you can never cash it in a bank.
You could only deposit it in your own account so make sure that you should have your own account.
You may still uncross it by making a signature at the ȁCpay to orderȁD portion,
which can be found at the upper left hand corner with the signature of an authorized signatory so you could cash the check.