I have baught a credit of 10 $. I want to convert it to skype subscription. Please let me know how to convert skype credit to skype subscription.
it is not possible to convert credit to subscription. Yet, if the conditions are met, I think you can request for your credits to be refunded (then later on use the refunded funds to purchase a subscription).
Below is the link where you can see the requirements and instructions on how to request for a refund;
What you can also do is purchase a subscription using your Skype Credit (or part of it) as a payment method. For this, during the purchase flow you will need to select Skype Credit as a new payment method ("S" in a yellow circle).