The United States Patent and Trademark Office (USPTO) provides a one-year period to convert your provisional patent application into a formal non-provisional patent application. If you do not convert your provisional patent application into a non-provisional patent application within that period, your provisional patent simply expires twelve months after its filing date. If you are still not ready to file for a non-provisional patent application at the end of the one-year period, you may be able to re-file your provisional patent – if and only if you haven’t publicly disclosed the subject matter of your provisional application more than 12 months prior to the re-filing date. However, you will only be allowed to claim priority to the date of filing for the re-filed provisional patent application, rather than the one that was originally filed.

If you are interested in more detail related to your situation it is best to speak with an attorney.