tortoisehg - how to rollback a branch merge in mercurial -

i have merged development branch production mistake. haven't made public, please let me know how can revert merge ? using tortoisehg workbench.

you can strip commit did merge, assuming it's last one. right-click, modify history -> strip.

if it's more complex that, post more detail (e.g. screenshot of graph) , i'll try help.