Thank You everyone for your kind advice.
Mine case seems bit different. My family name and my child's family name on passports are different. When CHC-Delhi issued visa they wrote family name similar to my passport family name not as my child's passport family name. Therefore, there is mistake on my children's passport bio-page and visa page. Then after we sent it for correction on March 18 as per the CHC-Delhi guidance, Unfortunately which I haven't received yet. We communicate via case specific inquiry, fax, and email but no response in this matter. More important visa has expired on May 13, so we are not having any communication from there side, hence what to do next? Has any one have/facing similar problem? please advice us-what to do next in this case?
Thank You