"I just sent you a message explaining what had happened. I am truly sorry. I am still sick so please ... " (more) give me just a week to get to the post office to send you the picture. Again I am very, truly sorry."
"I had a severe emergency and I have been trying to contact you but I think you blocked me. I still ... " (more)want to send you the sandals if you want them but I cannot do so if I cannot contact you. I apologize for the inconvenience, I truly do."