yobjectnotfoundexception

YObjectNotFoundException exception is thrown when we try and preform an operation on the cart even though hasCart() returns true. while saving the cart it searches the db for the cart with primary key and throws the exception.Could you please help with this as to why the hascart() returns true in the session when theres no cart with primarykey in db.And what can be done to avoid this.

if(carservice.hasCart(){ cartService.xyz() //here the exception is thrown while trying to make an operation on cnd finding cart by primary key in db } .....

de.hybris.platform.util.jeeapi.YObjectNotFoundException: Entity not found (pk =... name = '...' type code = '...' db table = '...')