In the case of a loss or a theft of cashless tag, the first question to ask is whether the user knows the short ID of the tag (written on the back of it). Either because they have made a note of it, or because they have already registered on Cashless.fr.
If it is not possible to identify the Cashless tag, then there is nothing else to do, this is equivalent to losing a 20 Euros bill during the event: anyone who picked it up will be able to use it.
If the Cashless tag can be identified then there are 2 possible cases
If the online refund is activated, the easiest way to manage a loss or theft is to direct the user to cashless.fr on which he can make a refund request. For the rest of the event they can retrieve a new Cashless tag that will be topped-up normally and can also be refunded with the first tag.
Attention
The balance that will be refunded will correspond to the remaining balance on the tag once the blocking has been done on all terminals of the event. If the balance is spent by another person this will not be refunded.
It is also possible to manually manage the case of a loss or theft by finding the user's Cashless tag on your back office and then blocking it manually.
Cashless System > Cashless Tags > Listing
To find the Cashless tag just type the short ID in the quick search bar to display the corresponding Cashless tag:
Then click on the block button 
It is possible to credit a new Cashless tag for the user with credits "litigation". (an Administration profit center is required) by checking the balance of the previous tag on the same page.
Caution !
The balance displayed on the back office depends on the correct synchronization of the terminals. It may be better to wait until the blocking command is successfully retrieved by all terminals before crediting a new tag
Info
In both cases, it is important to inform the user that the balance displayed on the back office or on Cashless.fr is not necessarily up to date and that it may change if another person uses the cashless tag before the complete blockage.