Hi @tuhin
Thanks for your concern. All servers have a limit of how many PHP variables can be used at one time, and how big an array variable can be.
Your repeater field is perhaps the larges I have ever seen, and this field was not intended to be used in this manor.
ACF does not contain a limit, but PHP does. It is possible to increase this max_vars
limit and PHP memory
like so:
http://www.advancedcustomfields.com/resources/faq/losing-data-save/
Thanks
E