Change background white

Information for the business: Jewellery company
Design details: Hi everyone, my name is Tanya and I own a jewellery company based in the UK. I have a header/banner for my social media but it hasnt been made very well as the background is not completely white. There are patches of grey from some of the jewellery photos that were added.

This seems like a fairly straightforward task and I imagine it would be a quick job for someone with Photoshop.

Once completed the photo should be sent back in jpeg format without any alterations to quality and/or size of image.

Please get in touch asap if you would like to work on this.

Thanks
Ideas for the visual style: white background
Where the design will be used: social media
Extra notes: