payment remembering mail

I’m testing sending payment remembering mails.

For example if I put this in a mail towards all persons who bookend for the event and who did not pay yet or did not pay the full amount yet.

Hi #_FIRSTNAME,

Totale price: #_TOTALPRICE
Already payed: #_AMOUNTRECEIVED
remaining to pay: #_AMOUNTREMAINING
Payment link: #_PAYMENT_URL

In the received mails the #_AMOUNTREMAINING is not showing. And if I clic on the payment url and for example go to the mollie payment gateway, the total price is shown to pay not the amount that is remaining to pay.

And also in the half of the mails the payment url is not shown. How does that come?

Could you help me so that the #_AMOUNTREMAINING is shown and the price in the payment gateway is also the amount remaining?

Looking forward to your response.

Greetings
Stijn