Misleading information about extra trade in value

Yesterday evening I wanted to switch to KPN both my home internet and my mobile subscription for two reasons:

1. Nintendo Switch 2 actie for house internet
2. Extra inruilwaarde € 150,00 shown for the mobile subscription change

Although the confirmation screen told me that a confirmation mail had been sent, I didn’t get it until the next day. Anyways when I got it I also got the Recommerce mail to send my phone back in 14 days (this seems to be another problem as customer service told me I would have 14 days when I receive my new phone not when I apply)

As I got the confirmation and Recommerce mail I have noticed that the extra € 150 is not shown anywhere and disappeared! I called the customer service and after a long 31 minutes call, I was told that it only applies for the Unlimited contracts which is not what I see on the web page when I apply. I can clearly see (and still can reproduce the same) via website. I select a limited 15 GB package and I get the extra €150 trade-in value as below:

So after all what can be done is to cancel this, select a higher package which is €4 expensive but much slower (selected 15 GB limited has 300Mbit speed vs the lowest unlimited has 50 Mbit) so I would save roughly another €54 in two years. For a similar experience (400 Mbit Unlimited) I have to pay €6.5 more per month which would end up 6 euros more in two years which doesn’t make any sense as the complete €150 extra trade-in value would be gone (as I don’t really need more than 20GBs at all anytime). Moreover I have some other vendors who can provide a better trade in value than what I got and a bit cheaper in the mobile subscription but as we all know it is better to keep everything in the same company to enjoy combideals. So as I really wanted to switch my house internet subscription to KPN, I would like to have my mobile subscription(s) on the same as well for the advantages on both.

So I do understand what the main reason causing this here but I do not agree with what have been shown is what I got. What I see above is a misleading information and very disappointing. I know I can cancel within my 14 days cooling off period but that is not the point here. In the end, what we see should be what we are buying. Not only disappointing but I do believe this is not even legal (to show something but sell something else).

I would really appreciate if this can be looked from my perspective and a reasonable solution (a new Recommence offer, a discount or anything similar, whatever it is) can be provided to me.