from Globes:

Manufacturing a matza shortage
Rami Levy: It seems there is informal agreement between the producers on how much matza they will supply and to whom.

The fierce competition between supermarket chains as the Passover holiday approaches is allegedly causing distortions in the market for the holiday’s most basic commodity unleavened bread, or matza.

Retailers that tried to order matza in the past few days have met refusal from the matza companies, who say they are short of stocks. On these grounds, the manufacturers are refusing to supply chains with which they have no exclusive agreement.