Sandisk Ultra USb 3.0 64Gb bad sector

Sandisk Ultra USb 3.0 64Gb disappear from USB port after copy file half way. Using EaseUS Partition Master found some bad area and after many bad area appear, it dismount from USB port. Try to use format partition, delete partition all not successful.
What should I do? How can I mark the bad sector like harddisk for me to continue use it. Although it is life time warranty but troublesome to go for repair.