Modify some code on wordpress site

Avg Bid (GBP)
Project Budget (GBP)
£20 - £250

Project Description:
We have an eCommerce site that works well for the sale of flowers. There are three different options for postage, the word press side appears to work fine, but as soon and will allow you to select next day delivery (which costs more than standard) and updates the price accordingly. The main issue is when the information gets passes through to pay pal no matter what is selected on the word press site pay pal always displays standard delivery and that price. There must be a bug in the code that needs to be found and resolved. The site in question is

Skills required:
Hire learning110
Project posted by:
learning110 United Kingdom
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