Amazon Tel call re account verification?


My account was suspended 3 weeks ago pending verification. I have been selling for over 7 years and uploaded my passport for verification but had problems with the files. So then my account got frozen.
On 23d July I received this email
“Currently your information is being validated. During the validation process, we will hold your disbursement. If we need any additional information we will contact you. If we do not contact you, the information will be verified within 5 business days.”
Nothing has happened yet except I got a telephone call on 1st Aug from a 0116 tel no. It was foreign voice from a call centre and I was cautious because I assumed it was a scam.
First the caller asked to speak to me, but before I said who I was I asked who was calling. He said Amazon and I then confirmed it was me and then the phone went dead.
Do you think this really was Amazon? Any advice about what I should do to get my account back up and running?