Experiencing Severe Turbulence, Not Able to Maintain FL

3 turns, word for word from the oral. Read the pilot lines out loud.

The exchange

3 turns in order

You, the pilot

Varanasi Control AIC-1229, unable RVSM due turbulence, passing FL 270, request FL 280

ATC

AIC-1229 FL 280 not available due traffic, descend to FL 260, Varanasi Control

You, the pilot

Descending to FL 260 AIC-1229