Awful service from Certus, they have been a provider for many years. Ordered and paid for oil upfront and when the driver turned up, he said our tank was unsuitable and refused to fill it? Same tank we’ve had for over 10 years and they’ve never had a problem before. We showed the delivery driver all relevant paperwork to which he said ‘so you say’?! So we say? The paperwork had our business name all over it! He was rude and refused to move his lorry for over half an hour blocking in our neighbours who were trying to get out. To add insult to injury, we’re still chasing our refund. Do not touch these with a barge pole, there are many better companies you can use