Hi Flor Arregui and welcome to the NS Community!
I am sorry to read that your train was cancelled! You can't use those tickets on another day, because the tickets are only valid on the entered day. It is possible to request a refund for a delay. You can fill in this form. If you want to travel again tomorrow, you can buy new tickets for that.
Nog maar weer eens: volgens EU regels MOET NS in dit soort geval-reis afgebroken en teruggekeerd-het hele bedrag vergoeden, niks 25% vanwege vertraging.
Apart from the EU rule there is also article 6.1 of the NS General term & conditions that states that if it may be reasonably expected that a delay on your Travel Route will last longer than 60 minutes you can exchange your single-use paper Ticket, E-ticket or Single-use chipkaart with NS for a comparable paper Ticket, E-ticket or Single-use chipkaart that is valid at another time of your choice. Or you can terminate your journey and request NS to refund the price of your single-use Ticket.
https://www.ns.nl/binaries/_ht_1611666465825/content/assets/ns-en/terms/general-terms-and-conditions-for-the-transport-of-passengers-and-hand-luggage-of-the-ns-avr-ns.pdf