T Icon to Add Text Does not Appear on the Side of the Block

You can add one text box per block when creating a video. Each text box includes a title and subtitle field. If the T to add text does not appear on the menu on the left side of the screen when working on your block, you already have a text box added to the block and you won't be able to add another. Click on the text box to edit the existing text or delete the text box.