Default Payment option for users with no account

I have 4 options of payment in one of my shops.
If a customer does not make an account, and complete the order with a guest account (adding name, address), at the next step, the payment methods don’t work properly. The default option, shown as selected is PayPal. The option that is shown in the last step of the checkout process is the second most recent.
So for example, if I select PayPal, then cash upon arrival, then Credit Card, the one that will be shown in the last step is cash upon arrival.
If I select from Paypal(default) to Credit Card, then PayPal, the one that will be shown at the next step is Credit Card.
They work if he/she chooses to login first.
Anyone has any idea what the issue could be?
Thank you!