The behavior described is consistent with corrupted or misconfigured list formatting rather than a permanent loss of multilevel capability. Restoring proper multilevel behavior typically requires redefining the list formatting and ensuring the multilevel list feature (not the simple Numbering button) is used.
Use the multilevel list definition dialog to reset the list:
- Place the cursor in one of the list items that is misbehaving.
- On the Home tab, in the Paragraph group, select the dropdown next to Multilevel List (not the simple Numbering button).
- Choose Define New Multilevel List.
- In the dialog, click More to expand all options.
- For Level 1, set the number style, alignment, and indent as desired.
- For each subsequent level (2, 3, etc.):
- Select the level in the list.
- Set Number style, Number format, Alignment, and Text indent.
- If needed, link the level to a heading or paragraph style using Link level to style.
- Use Set for All Levels to apply consistent alignment and indents across all levels.
- Confirm the Restart list after options are correct for any levels that should restart numbering.
- Click OK.
After redefining the multilevel list this way, apply that multilevel list to the paragraphs instead of using the simple Numbering button. This ensures Word treats the list as a true multilevel list and prevents it from reverting to a single-level numbered list.
If the issue persists across documents, create and save a list style based on this multilevel definition so it can be reused consistently:
- After defining the multilevel list, save it as a style.
- Apply that style in new documents instead of manually recreating the list each time.
If numbering or alignment still appears incorrect (for example, extra space when numbers reach two digits), adjust indentation via Define New Multilevel List as above, since that dialog provides full control over number alignment and text indents.
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