I recently opened an Amazon account on my tablet/phone due to books taking shelf soace up.
I've got a thirty quid balance from top up cards but my problem is this, it won't download books and deduct from my balance and I keep going sent back to the buy page.
Anybody know what's going on?

You may need to explain further what you are trying to do.

What are these vouchers? Are they definitely part of your Amazon account balance?

The other thing to watch with Kindle books is that Amazon will keep trying to persuade you to subscribe to Kindle Unlimited. It's very easy to hit the wrong button and be sent to the sign-up screen for Kindle Unlimited.

Do you have the Kindle app on your phone/tablet?

I haven't responded because my pleas for help (they atre genuine) don't get much response.
The answer to both questions is yes and I have the Kindle app on my phone and tablet.
What T want to do is downloads as many of my favourite books and films as possible due to shelf space (even dolanloads take space up).
I've sorted the problem out with debit card.

Can you buy books from the website, rather than the app? i know on some platforms the app is rather limited.

Did you get this issue sorted yet? Have you be able to spend you're gift card balance?

According to the Amazon website to use a gift card for digital downloads, do one of the following:
- Redeem your gift card in Your Account
- Click Redeem a gift card or promotion code before clicking Buy now

Once your gift card has been redeemed to Your Account, the balance will automatically be used to pay for your downloads.