Incorrect display/loading of the survey

A Kobo form with 140 questions was created and launched. About 70 people filled out the questionnaire. Then, 7 questions were added to the end of the questionnaire and grouped together without a title.
After that, the Kobo form began to display incorrect information when displaying and downloading data (for example: 1. where the year had to be entered, it replaced it with numbers with underscores between the numbers. 2. where there used to be a column with a header, there are now numbers. 3. some columns have disappeared. These are the main problems).
The form contains a large amount of logic for different questions + logic for displaying a group of questions.
Additional information: there is another Kobo form with up to 15 questions, and one question was added at the end. About 100 people took part in the survey before the changes. After adding the question, the Kobo form works normally and everything is fine.
Question: Why did this problem arise in the large Kobo survey? And what do you recommend doing in the future to prevent this?

Welcome to the community, @anastasiiya! Could you kindly share with us a screenshot of your issue so that we could understand it pictorially and start investigating if it’s an issue?

Hello. For example, there should be information about the year of creation here.