It's already a promotional offer and as such further discounts cannot be used, the only different answer you might get is from someone who doesn't know the correct info. It cannot be applied to a promo anymore and any promises to do so cannot be trusted.
The rules changed as of 29th August 2024 on this discount eligibility when the Tariffs were refreshed, but the family and friends discount was also changed in the last year to offer 50% off Airtime or SIM Only.
You can use it on the full-priced £48 Full Works plan which would take it down to £24, as this is the core price plan and is the only one eligible for further discounts. This is what I have done and I'm beyond happy with it.
I don't think you should be disappointed with the value on this SIM, you get the choice of a benefit worth up to £20pm (or £18pm in my case for Netflix Premium which i paid for previous) which means in my experience my net spend for my SIM is 6 quid compared to before...
Alongside getting roaming in the EU, US, Canada, Australia, Mexico and New Zealand (and possibly more soon if they expand to the ROW Zone 1 countries).
Also free watch data if you have a data capable smartwatch that you need a plan for.
There's more benefits on there too, like 5G SA and Network Prioritisation.
£29 is incredible value for this without needing to know someone for a discount.
