Are these outline-numbered headings? In that case, note that Word adds a tab character for the text following the heading number and a second tab character for the page number. What you should do is set the two tab stops in appropriate locations, not try and remove them.

Alternatively, if you really want to get rid of the tabs, you will have to modify the numbered list of headings so that outline/multilevel numbers are followed by a space instead of a tab stop, and you need to customize the TOC so that the page number is not right-aligned.

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Stefan Blom
Microsoft Word MVP

Microsoft 365 apps for business
Windows 11 Professional