Pound World in Plymouth

When visiting Pound World (Armada Way) on Thursday 18 August 2016 and tendering £20 receive change for £10 (immediately pointed out to cashier). Upon contacting manager for CCTV confirmation (cctv is not clear!). Promising to ring me back. On phoning today (all calls logged on my phone) Pound World say they rang me at 19:10 on 17 Aug to tell me til is spot on. When handing over cash please be clear to state clearly the value of the note you are handing over. By the way, there was no call logged for 19:10 on 17 Aug.