mishandle
🇺🇸
/ˌmɪsˈhændl/
🇬🇧
/ˌmɪsˈhændl/
to not handle something properly or to make mistakes when dealing with a situation
The manager mishandled the situation, causing the project to fail.
to treat something or someone roughly or without care
The delicate vase was mishandled and broke into pieces.