If you upgraded to Spectrum Technology Platform 2022.1 from an earlier version of Spectrum, you will need to reindex 2022.1 indexes before you upgrade to Spectrum Technology Platform 2023.1.
For instructions to do this, see Reindex 2022.1 Search Indexes before upgrading to 2023.1 under "Upgrading your Installation" in the Spectrum Technology Platform 2023.1 Linux or Windows installation guide.