[Vuejs]-Currency amount must be non-negative number, may optionally contain exactly 2 decimal places separated by '.'

Afterwards I found the issue, I was follow the GitHub steps:

<PayPal
  amount="10.00"
  currency="USD"
  :client="credentials">
</PayPal>

the 10.00 is the given number, I’m passing a variable, I should use the

<PayPal
  :amount="amount"
  currency="USD"
  :client="credentials">
</PayPal>

Then I solved my problem.