If that’s the CMS hosted with Spring Singage, then I do have access to it.
The longest duration on your layout is 30s, which means regarding your text issue
3s - first text
20s - second text
3s - first text again
around 4s - second text again
Please have a look here: Understanding Media Duration and how it affects the playback of a Layout
You might want to adjust the durations and please test it on the device as well, preview is not ideal and might not reflect the exact layout playback you can observe on the player.