Is the available stock indication reliable?

Yes, from 04/01/2021, every day in the morning there is a review of the available stock.

Obviously we are talking about a process that is carried out by humans, so an error can occur.

It is not very likely to happen, but when the product indicates that there is only one unit, it may happen that at the same time the product is being bought by another person and the first person to complete the payment is the one that will finally be served. If this happens, we will refund the money to the customer who has not been able to serve it.