I have accidentally deleted the images in my memory card! camera model: DSC W350 and if try to download the recovery software from sony website its not detecting my memory card model no. my memory card model number is SF-4C2 kindly help

You may take the memory card out from phone, and then use a memory card recovery software, recommended asoftech data recovery that helped me before, you may refer to this tutorial
How to recover images from memory card

If above does not work, you may have to format the memory card (use quick format), and then use above mentioned software to scan again the memory card and recover your files.

First take the memory card out of the camera. Pictures that have been deleted are probably still there, but will be overwritten if you take any more pictures on top of them.

Your camera is not able to undelete pictures, but there are programs for doing this on a computer. You can put the memory card into a card reader attached to a computer, and use an undelete program to recover the deleted files. Undelete programs are available for free download from the internet, try the one at THIS LINK

If the pictures are very important to you, you might want to seek help from an experienced person.

Two more tips added:
1. Stop using the card immediatelly and don't even attempt to write any data on it;
2. When you have recovered the photos, do remember to save them another disk instead of the card itsself.

These are very important if you want to raise a little more chances of rescuing more images. You can also see this article to learn more detailed steps and helpful tips. Regards