Yes. You can do it via your settings.
You'll lose your calling credit if you switch. Best thing to do first is cancel your automatic payment if you have one. You can do that here. Afterwards, use your bundles and your calling credit BEFORE switching to a subscription.
If you're already on our new platform (you'll know when you've received an SMS about it), you will keep your bundles (meaning your mobile data and texts) if you switch.
If you're not yet on our new system, you will not keep your bundles.
Can I switch from a prepaid SIM card to a subscription?