Started a website however gift cards and coupons not working?

Hello,
I have been setting up a website and have installed a gift card plugin. The gift card is set up but when purchased the code does not work. It states minimum spend ￡10.00 but this is on items over ￡200.00. I contacted the plugin uses who checked on my behalf and confirmed this was not a plugin issue. They did set up coupons aswell and again the same message came up.

Is anybody able to identify this issue and help resolve? Thank you.