The lidl app is a total rip. When you manage to spend over the target amount (£100 or £200) in any monthly period and receive a £2 or £10 coupon you can only redeem it at the next shop. Invariably by the time you get the voucher you have just a matter of days left to go shopping again before it becomes inactive, thereby forcing you into shopping early.
This is a cynical, unfriendly and self serving product by Lidl.