I have open wound under my armpit from abscess. it already pop. what to use to help heal wound cause it doesn't look like it's healing completely?

Sweat gland infectio: You might have had sweat gland infection/abscess. It usually heals if not need to rule out infection with resistant bugs like MRSA. Have it cultured and treated appropriately.

Heat pack: Moist heat pack and keeping wound clean and out of water can help speed the process along. If it is not progressing over next few weeks should see someone.