If an individual or institution avoids service of court processes, you can go back to court and ask the court to order substituted service.
Obviously with a Bill passed by Parliament, substituted service is not possible because the President has to assent to the copy transmitted by Parliament.
The only option Parliament has is to go to the Supreme Court and ask the apex court to declare the President’s refusal to receive the Bill unconstitutional and ask the SC, among whatever reliefs, to order the President under Article 2(2) of the Constitution to receive the Bill. If so ordered, the President would have no choice but to obey, failing which he can be removed from office under Article 2(4).
So let the NDC and President Mahama stop the purposeless lamentations about a threat to our democracy and rather ask Parliament to head to the Supreme Court.