Table of Contents Oversetting

Open the TOC in Story Editor and look at the first pat ofg the overset text.

Common reasons for oversets like this are you haven't allowed words to hyphenate and used a string or non-breaking spaces between or applied No Break to a long string that results in a string of text that is unbreakabe and wider than your column. I've also seen cases where left and right indents combined left insufficient space.

Hard to troubleshoot this one as it could be a paragraph style

It could be a text wrap

It could be an unintended space before/after

Hard to know without seeing the file itself, screenshots or videos etc.

In the meantime

If a document is not behaving well then try 

File>Export 

Choose IDML

Open the IDML in InDesign
Save the file as a new InDesign file with a new name
See if the issue persists.

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Try resetting your preferences:

Windows: Start InDesign, and then press Shift+Ctrl+Alt. Click Yes when asked if you want to delete preference files.
macOS: While pressing Shift+Option+Command+Control, start InDesign. Click Yes when asked if you want to delete preference files.
A dialog will appear asking to delete the InDesign Preferences, select 'Yes' on this dialog.
Further info and instructions here if needed:
https://helpx.adobe.com/in/indesign/kb/indesign-preferences-support-file-locations.html

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Reinstalling rarely fixes everything - you can do a complete reinstall using the
Creative Cloud Cleaner Tool https://helpx.adobe.com/creative-cloud/kb/cc-cleaner-tool-installation-problems.html