Hi Tanvi,

For this, you have to create a new validation attribute and then you need to apply this new attribute on your property. I already answered your last query you can refer that.

https://world.episerver.com/forum/developer-forum/-Episerver-75-CMS/Thread-Container/2020/6/how-to-limit-number-of-elements-in-ilist-with-only-minimum-elements-value/

Pasting here the same answer-

http://www.iceninemedia.com/articles/limit-the-number-of-items-allowed-in-an-episerver-propertylistt/

https://world.episerver.com/blogs/Allan-Thran/Dates/2017/11/limit-number-of-elements-in-a-linkitemcollection-or-contentarea/

https://world.episerver.com/blogs/aniket-gadre/dates/2018/10/max--min-validators-for-content-area-or-link-collection/

[ListItems(2, int.MaxValue, ErrorMessage="At least two items, please!")]
public virtual IList<QuestionnaireAnswerBlock> Answers { get; set; }

Or, if you want full control, you could create your own custom validation:

https://www.jondjones.com/learn-episerver-cms/episerver-developers-tutorials/episerver-content-areas/how-to-create-a-custom-content-area-validator-in-episerver/

 [ListItems(2,6,ErrorMessage ="Minimum 2 and Maximum 6 columns are allowed")]