I have signed a contract for 5 years for a contract that has one name and now two years later that company has changed names.

 A change in the name of the entity would not affect the validity of the contract except in very rare instances where the name of the contracting party was a material term of the contract - I can't even think of an example off the top of my head.  In fact, unless the contract prohibits assignment, or is of a type which can't be assigned by law (for example, a contract to perform personal services), the contract would remain valid even if, rather than the contracting party changing names, it was assigned to an entirely new company.