Reminders of signing up for warranty despite already have

My phone keeps giving me notifications reminding me to sign up for the extended warranty. The thing is I already have, weeks ago. How do I make my phone realise that? It seems that Fairphone 4 had the same problem but I couldn’t find any suggestion besides “ignore that notifications” or “turn off notifications here” but I want the system to give me notifications of things I need to know, it’s just this specific notification I want to get rid of.