This is one of the most common phishing scams, which involves scammers posing as a representative from a well-known company. Some scammers will even re-create the original webpage in order to trick you into clicking the link provided in the email.
By clicking the link and entering your username and password, you have essentially given somebody else access to your account. They can then log in as you and withdraw any funds you might have.
If you have concerns about any of your accounts, either call the company or go to their website by manually entering the URL rather than clicking the link. Most companies will have information online about how to identify genuine communications from them, and equally any scams they are aware of that use their company name.
For more guidance on how to stay protected online, take a look at the tips on Paypal's What is Phishing webpage.