Does this count as theft?

Assalamu alaikum! I’m a 17 year old, currently into botting online stores, in order to purchase goods that are in high demand, which in turn, allow me to make profits, etc. And i was wondering, if it is haram to use discount codes more than once on the same account. For example, “Zalando” an online store, gives away free 10% discount codes, for each new customer and in their policy, you’re not allowed to use it more than once. Would it be haram, if i used that discount code more than once, on the same account? Would it be counted as theft? Etc…i can get those discount codes by creating multiple accounts, and using them on my old account. Those discount codes really help me in reselling, if a shoe costs 200 usd, i save 20$ on it, and in that case, i make 20 USD more, insha’Allah. I’m really worried, that this would count as theft, and would render my income as haram.
I tried to think on my own, and found other examples similar to this. Let’s say a nearby supermarket makes a sale; “TWO CHICKEN LEG PIECE PACKS PER PERSON”, and you find it very cheap, and would like to stock up on it. So you, call close friends, and tell them to buy those two packs, for you to pay for, and also keep. Would that count as theft, since i’m utilizing a discount, and paying less, even though i’ve used the discount, more than my allowance. (if this exemplary scenario is irrelevant, please ignore it :D)
JazakAllahu Khairun!