How to handle random multiple requests from the frontend on the backend?

Question

Backend

There is an application. A client on a mobile phone enters data on completed tasks for the day, sends a request to the server. The application adds an entry to the database and returns some kind of answer (% of work performed from the norm per day, for example).
One of the customers clicked on the submit form accidentally several times in a row.
In what ways can the back handle this situation? If the front can not touch.

Answer 1

If you can not touch the front, then as the only possible option - to throw an error on all subsequent requests, or to limit requests.
If you can touch the front, then there are different options:
https://habr.com/ru/company/yandex/blog/442762/