We are based in London if this is any help to which rpl company will send me a letter

Hello. Last week me and my friend were caught shop lifting from Debenhams. We are both over 18. A policewomen came to speak to us but no criminal charge she was happy to not press charges. We are both banned from debenhams stores for a year but Debenhams handed us both a letter about 'Civil fines'. The security guard at Debenhams claimed in the letter we will both be fined £300 each, although what we attempted to shop lift came to around 70 pounds each. We are both extremely sorry about doing this and would never do it again. Debenhams said they caught us on the CCTV cameras. I have researched into these Civil Fine letters and all I see is people saying to ignore them and not to pay, should I just ignore? I am worried as Debenhams have cctv footage the civil company could take us to court. Also, when the letter comes in the post will it be a privately addressed letter with no company logos on? As I live with parents and wouldn't want them to notice anything funny on the envelope. Thankyou!