ffmpeg: Image + Audio + Text to Video

I'm new to ffmpeg and am trying to create a video (mp4) by combining two images (png) and an audio file (mp3) and overlay it with a text.

I can successfully create a video by combining the images and audio but I struggle to add the text.

Here's my script to overlay on image with another and add the audio:

ffmpeg -loop 1 -i background.png -i overlay.png -filter_complex overlay -i audio.mp3 -shortest -acodec copy -f mov video.mov

How can I add an overlay-text to the video? The text remains unchanged for the entire video.

Thanks in advance.