I always heard an advertisement of #Mobiclaim on the radio. And that aroused my interest;) Just figured out: if you signed a subscription with a 'free' phone between 2012 and 2017, you can request a refund via that website. You send a copy of the contract or a screenshot of the confirmation email. It seems to take a few months before you hear whether or not you qualify for a refund. It is based on no cure-no pay: only if you get a refund (the new price of the device - the daily value) you pay Mobiclaim 30.25% (25% + VAT) on the amount to be received. You can get a maximum of 750 euros back for your old device (which you don't even have to own anymore. The provider determines the daily value of the relevant smartphone). Mobiclaim is not intended for business subscriptions.

I have just sent a scan of my contract (August 3, 2020). Now it's waiting...
Small update: I received an email from Mobiclaim (August 4). Mobiclaim's lawyers had already reviewed my claim. The probability of success is real, it says. I was advised to search my inbox for other renewals (with free device), because my current claim is from a 2013 subscription (with smartphone), but I don't have one (idd, I still have my Samsung from that subscription):)

About Mobiclaim
Mobiclaim was founded after the #hogeraad had decided that it was unfair that you had to pay for “free phones” anyway. The initiative comes from #pieterbrouwer and #jochemvandalfsen , two entrepreneurs who include #slimleren have been started. This learning platform has been named #besteeducatiewebsite of 2019.

https://www.mobiclaim.nl/