Plugin Stuck at 1000 records - Wordpress

I am using a free plugin that is used to redirect zipcodes to the links of our choice, it worked perfectly till 1000 postcodes, but now its not adding more, if i add more zipcodes from the database then it works fine, but saving settings from the page removes the ones added from database, Kindly write 'got it' in the bid to make sure you read the description carefully and you can work on it.