Minimum spend not allowing me to make purchase on Galaxy Store

[F55]

I have a £3.61 voucher remaining on the Samsung Galaxy store and I can't purchase an app that costs £3.74 because the app does not allow me to pay the different of £0.13. A message appears saying there is a minimum spend of £0.20. 

I tried several payment methods (Samsung Pay, Visa card, Amex and PayPal) and each message specifically says: 

"The minimum payment is £0.20 when paying with Samsung Pay"

"The minimum payment is £0.20 when paying with Credit card" (says this for Visa and Amex)

"The minimum payment is £0.20 when paying with PayPal"

I'm assuming this message is linked to the Galaxy Store having a minimum payment requirement, and not that it is linked to the payment method itself.

The only payment method I've not tried is PaySafeCard because I haven't signed up to it - I would sign up to it if it worked to make the payment for the remaining £0.13, so will it? Or is there any other way around this? I don't even mind making the minimum £0.20 payment but of course it doesn't give me an option to do that. 

It's rather silly being issued vouchers by Samsung as an incentive when they can't be used on the apps you actually want, especially when there are very few interesting apps to buy in the first place from Galaxy Store compared to Play Store. You always lose the voucher in the end because there's nothing good to spend it on or the remaining balance falls slightly short of an app you finally find you want.

[GoanGeek]

Use it to buy fonts. That's what I did.
The Samsung Store is really useless and not worth it even with the free vouchers.

[F55]

I know I can buy wallpapers but never thought to buy fonts since I'm normally happy with the standard font, but I will check it out.

[Baguvixx]

I had the same issue and fixed it by adding more credit to my Samsung Wallet. Once my balance was over the minimum spend limit, the purchase went through without problems.

[F55]

I've never known the wallet to take credit. I thought it was just simply for card payments rather than to store money? On looking at the app I can't seem to see an option to add credit.