promotions company seeks advice

I own a promotions company in the Port Elizabeth, we have been operating for 3 years. Our core focus areas are promotions, brand management and events management.

We have conducted promotions activations, events and brand activations for nationally and internationally acclaimed companies. HOWEVER these contracts were mostly subcontracted from other promotions companies in my city.

Most companies that acquire the services of promotions companies are located in JHB or Cape Town. These contracts are then awarded to companies that can activate promotions nationally. These promotional companies then subcontract these contracts to promotional companies in my city that they have formed alliances with years ago.
And the circle continues, leaving very little hope for anyone to come into the market.

I have submitted proposals to most companies and followed the trends with regard to new products and brand activations. The response stays the same (we have appointed a national promotions company to activate our promotions.)

My question is...
1. How do I break into the market, when companies mainly awarded contracts to promotions companies that can activate nationally?

2. How do I subcontract these contracts, when national promotions companies have formed alliances with companies in my city years ago? And it seems like these alliances cannot be broken.