I've had an email from the above company asking me to update my details. I've recently had a new bank debit card and I activated it yesterday. It said in the email that I've got a new card, how do pay pal know this? Is it a coincidence or a scam?
They would know that your old card was out of date from the records held Melv. Do not log on from the email link. Open a tab with a search or use your bookmarked link if you have one.
Do you really mean an email or a paypal message? Paypal put such requests as messages on your paypal home page. An email is probably a scam. If it is an email here is how to check if it is genuine
https://www.paypal.com/jm/webapps/mpp/security/report-problem