Ransom is due on the one who is in the state of Ihraam if he does one of the following things:

1-    To commit one of the actions forbidden during Ihraam.

2-    To leave one of the obligatory acts of Hajj or ‘Umrah.

3-    To be a performer of Hajj At-Tamattu‘ or Al-Qiraan; and in both cases, the slaughtered animal of ransom is offered by way of gratitude and not of amendment.

4-    To miss Hajj or be prevented from performing it.

As for the ransom that is due because of committing one of the forbidden actions, it differs by the difference of the forbidden that is committed.

https://islamstory.com/en/artical/1823/reasons-ransom