Go to Plus help Preferences and make sure “Accept the Scrum for Trello format." is checked. This will let you see your “old" S/E/Points in your cards and boards. This setting helps you transition to “Plus" by letting you see your “old" S/E, or if you wish to keep two separate systems (Points and Spent/Estimate hours for example).
The main concept to keep in mind is that systems like “Scrum for Trello" use card titles to store Spent/Estimate/Points. Plus for Trello supports that and also a more complete system using card comments (or Google sheets) to keep track of S/E changes with traceability and accountability.
Thus, there are two types of S/E: “Card title S/E" and “Plus S/E".
Note that “Card title S/E" only shows in Trello boards, it does not show in Reports.