That looks completely normal. I have no idea why this is happening.
If I was investigating this, my next steps would be to look at the data directly in the database. I'm not sure if that is something you are able to do.
In particular the quiz_slots table (which roughly corresponds to the data in your screen grab, and the output of this DB query: https://docs.moodle.org/dev/Overview_of_the_Moodle_question_engine#Detailed_data_about_an_attempt for the two attempts of interest. Actually, I would add quiza.layout to that query. That might reveal an explanation.
If I was investigating this, my next steps would be to look at the data directly in the database. I'm not sure if that is something you are able to do.
In particular the quiz_slots table (which roughly corresponds to the data in your screen grab, and the output of this DB query: https://docs.moodle.org/dev/Overview_of_the_Moodle_question_engine#Detailed_data_about_an_attempt for the two attempts of interest. Actually, I would add quiza.layout to that query. That might reveal an explanation.