District Brain Hemorrhage Certified Letter From District Court?

Certified letter from district court? - district brain hemorrhage

I received a note from Saturday to a letter from a local court in the judicial district office received. If I am to be called as a witness to something that I saw, I sent it? Or what else to send a letter? I can not do so until tomorrow, and I lost my brain tries to find out what might be, please give some options that will be sent for.thanks