Paypal may cancel your subscription for many reasons. Some of these include: your main credit card may have expired on your account or your bank details may have changed. If this is the case, please add a new credit card or fix your banking details via the Paypal website and resubscribe to Mysterious Universe.
Unfortunately we are not provided with this information by Paypal so we are not able to assist with the more sensitive aspects of your Paypal account. However, you can access all of this information yourself by heading to your Paypal profile.