Input string was not in a correct format. Entity Fromework 6 (no replies)

Hello, I have been trying to solve this problem for a long time, I don’t understand what the trouble is.
I am using ORM Entity Framework 6, DB MySQL. I used the project for about 2 weeks, everything was fine, it was suddenly an exception arose today. It occurs when creating a table,i.e in context.SaveChanges();