A user is attempting to split a User Story by checking the split checkbox. After some time a message appears “the user story was being deleted by another user”. This is not the case! Nothing was deleted, but the story also wasn’t split.
Splitting of User stories can be an intensive database operation, the most expedient way to work around this issue is to simply copy the user story as follows;
1) Copy the user story instead of splitting it (a new FormattedID number is generated for the new story,
2) Mark the new copy as Unfinished and retain the "completed" tasks only.
3) Move the original story to the next sprint and mark as continued with "In Progress" tasks only
4) Parent the stories as appropriate.