Payment disappearing

Description

I recently updated some of my payment options and today went to pay someone. 2/3rds of the way through it I was asked to update my address which I did and then the transfer disappeared and it’s telling me I haven’t got any transactions.
How can I tell that it is Paypal and not a scam?
How can I tell if the money went through or not given it disappeared?
Are there any real-time service staff to chat to? I sent a message and it said we will get back to you in a few hours- is that normal for them?
thanks
Michele