The contract you signed may have a "force majeure" clause that explains what extraordinary circumstances void the contract. If the contract has no such clause, you may still argue:
- Frustration of purpose: when the purpose of the contract (for you) is destroyed by unforeseeable circumstances.
- Impossibility: when it is impossible to perform the contract (for the wedding company) due to unforeseeable circumstances
- Illegal contract (maybe): Illegal contracts are unenforceable. However, the contract was legal when signed (pre-COVID restrictions), so I would have to look into how this applies.
If the money you paid was a deposit, different rules may apply, but this gives you some direction in terms of answering your question. A lot of contract attorneys are debating this very issue, since COVID has created widespread issues regarding cancellations.
