The Appsheet itself changes the ID value

[bamalt]

Hello!
Strange things are happening in my program. I created a table with columns ID, Value. I filled it in from google spreadsheets, inserting the lines I needed (there are many of them for manual input through the program). This table is now the parent table and has a relationship with another table. Periodically, Appsheet shows me a warning that there are duplicate ID values ​​in the parent table. I fix them and later new takes appear.
A little about ID values. I generated them using an online UUID generator (128 bit). Then I trimmed to the first 8 characters and removed the duplicate values.
What am I doing wrong?