So it sounds like this issue: Internal error at D:\a\audacity\audacity\libraries\lib-wave-track WaveClip.cpp line 174. · Issue #4653 · audacity/audacity · GitHub
which to my knowledge there is no solution for.
Other than adding your report to the github issue, there are three things that may be worthwhile trying:
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Ctrl+A=Select All, Ctrl+C=Copy, Ctrl+N=New Project, Ctrl+V=Paste (skipping smart clip copy). See you have the same issue with the new project.
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Attempt the Audacity Recovery Procedure on your project - just the first post here: Corrupt or Otherwise Broken Audacity Project Recovery
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See if you have the same problem with the Audacity 3.4 Alpha which has NOT been released yet: nightly.link | Repository audacity/audacity | Workflow build.yml | Branch master
Disclaimer: The Alpha is untested and may have serious known or unknown bugs. Do NOT use the Alpha for any production work.