I'm trying to apply to retake my salesforce admin exam but it doesn't let me. A prompt shows up saying im already registered for this exam but I'm not.

@Bryan Solano :  

You can contact the Salesforce support for exams at : https://help.salesforce.com/s/support

Alternatively, you can also contact kryterion support either by email or chat at : https://kryterion.my.site.com/support/s/contactsupport?language=en_US

They will be able to provide you more information and possibly help with rescheduling. 

Hope this helps. Thanks!