genetic algorithm - initial population

I'm using global optimization toolbox for ga.

The lower and upper bound are 120<=x<=1360.

There is a problem for generating initial population: The first individual of the first population is being [120 120 120 120 120 120].

There are linear constraints, but it is the same with boundary.

I have read that the many initial individuals are around the boundary when the linear constraints are used in below:

https://www.mathworks.com/help/gads/genetic-algorithm-options.html#f14223

Please help me.

Thank you.