When posting a question can you please give the fulll version number. You find it under Help, About Captivate. Present version under CP2019 is 22.214.171.1243 for Windows.
Do you know that the only pdf Captivate can create is an interactive pdf, which was based on SWF-technology. Since quite a while Adobe Reader no longer has the SWF plugin and those interactive pdfs are not really functional anymore, especially now when Flash Player will no longer be supported end of 2020.
Can you insert a screenshot of your Publish settings, in case you insist on publishing to interactive pdf?