There are a lot of different mailing addresses and lockbox facilities that accept and process Form I-131, Application for Travel Document. Where to mail your Form I-131 depends on your status, for example, the mailing addresses differ for applicants with a pending Form I-485, abused spouses, children, or parents, Haitian or Cuban family members, U.S. military family members, T or U visa holders, etc. Also, there is a separate filing address for the purposes of correcting a USCIS error on travel documents.
So in order to determine where exactly you must mail your Form I-131, you should visit the USCIS official website and consult the chart called “Direct Filing Addresses for Form I-131, Application for Travel Document” (https://www.uscis.gov/i-131-addresses), simply choose from this chart the filing address applicable to your particular case.
Please note that there is an additional option. If you want to receive a notification (an e-mail or a text message) confirming that a USCIS lockbox facility has received your Form I-131 in due order, you may additionally complete Form G-1145, E-Notification of Application/Petition Acceptance, and attach it to the first page of your I-131 application.