To change text color, follow these steps:
Select the text, and navigate to the properties panel on the left
Navigate to the 'Color by' dropdown menu, and change the option from 'Layer' to 'Self'.
Choose the color you want by selecting the color bar that appears beside the 'Color by' field, and entering the desired RGB/HSL/HEX code, OR selecting from the gradient or the color picker tool.
Click outside the gradient box to apply the change.