Knowledge Base: Why are statistics missing missing from Text-Only campaigns?
In text-only campaigns, emails are sent without images or redirect links that allow us to track opens and clicks in your campaigns. This is more of a limitation in text-only emails and a process of keeping your emails clean.

For text-only reports, you will notice that open and click data is removed by default. If you wish to track open and clicks in your campaigns, you may use the "from scratch" or "template" options when creating your campaign content.