Employment Visa is not valid

I am Sri Lankan, I got an offer letter from a big company for the post of Electrical Engineer, and they required my passport copy and medical report, I had sent all that (and the medical report was expired before 03 months, but I have changed the expired date and declared is valid by my self), after two three days, I found in the LMRA express service that my visa is under process, and again after 20 days, when I check my Visa in LMRA, the Legal Status sayin, Employment visa is not valid, but before that days It was Employment visa is under process.

So please explain some one regarding this, why the Legal status saying Employment visa is not valid

Dear acawaaseeth,

Please contact your potential employer only they can know the reason for the same.

T&R