How to restrict the removal of only the first value in 'List' field type on form?

[Akshata_Shelar]

Please have a look at the screenshot.

So here I should not be able to remove only the first value of ownership group manager field, removal should be restricted but I should further be able to add and remove managers in ownership group manager field.
Please help me with the solution on this issue.

I greatly appreciate your help.