change the text box size

I use both, as at times I do want solid boundaries and that means a box.

Make sure you have the "selection" too, the arrow icon or select by clicking outside the Program monitor and tap the V key. Now you should see a blue line around your text box. With the dots for corners and sides. Grab a side dot & drag to change that side.

Click inside the box, and drag to move the box.

Neil

I personally don't like text boxes in Premiere because they cause problems like this.

I usually just click to get the cursor and paste without using a text box. Format the text after pasting.

For me this saves headaches.