https://tfl.gov.uk/fares-and-payments/oyster/using-oyster/touching-in-and-outThe following part may well apply to you...
Between 2 and 30 minutes: the minimum pay as you go fare from that station
You may be eligible for a refund if you have been charged for a same station exit. Speak to a member of staff, go to replacements and refunds or call us on 0343 222 1234 (08:00 to 20:00 daily
That's just how the chaos at Paddington, with sudden swapping of platforms, cancelled services, and use of platforms with no
Oyster▸ , cons the public.
So what's cheaper - spending your time trying to get a refund, or holding on for hours on a premium rate phone number? Or simply not bothering - as I guess most passengers do. With your situation its not your fault - but you lose anyway - that's the way Oyster is designed - and is why
TfL» has £14 million in its coffers. Fraud - you bet.