If you already have this written contract with "down payment for delivery of goods and delivery period", you can fully defend your rights according to this clause, or you can directly appeal to the court to safeguard your legitimate rights and interests;
Without the contract mentioned above, things would be more difficult. In case someone denies that you paid the deposit, you have to go to other places to collect written evidence that you did pay the deposit. If you can't get it out, the company denies that you paid the deposit legally.