Hello,
A few other customers have experienced something similar. Please take a look at these posts and let me know if it resolves the issue you're experiencing:
https://turbotax.community.turbotaxonline.ca/questions/1099499-when-filling-out-your-payment-form-i-...
https://turbotax.community.turbotaxonline.ca/questions/1100103-how-do-i-enter-my-credit-card-info-th...
