Restaurant owners in New York City say they're feeling the impact of the new vaccination proof mandate after it went into effect last week.

Cypress Hills restaurant El Rey tells News 12 that the place is usually packed - but has been seeing fewer customers due to the Key to NYC mandate.

Businesses, like restaurants and gyms, now must ask their patrons for proof of vaccination against COVID-19.

Restaurant owners say it's hurting their staff and business. An altercation between a hostess at Carmine's in Manhattan and a customer was caught on camera last week.

The owner at El Rey says one of his staff was also verbally assaulted by a customer who was turned away for not being fully vaccinated.

Restaurants that do not comply with the mandate can be fined up to $5,000. Restaurant owners say they're worried that their business won't last through the cold seasons.