ich war ausgetrickst beim O2 verkaufer

Hello O2 my name is Hermz. I currently work here in Germany and i applied for an O2 plan. I currently dont have residence permit or Aufenhaltserlaubnis yet but the verkaufer agreed to give me a plan if i pay in advance using my bank Konto. So i agreed to pay 181,00€ and i found out that its deducted to the 950€ gesampreis of the s10+. Gut kein problem. My problem is, i took the plan M(x2data) which is 20gb per month for 35€ monthly. But now im paying for an additional 81 euro for what? The verkaufer also gave me another sim which I ABSOLUTELY DONT NEED a data card with plan S. I think the verkaufer totally tricked me because my Deutsch is not that good. My friend took the handy plan L which is 45 € per month and he is only paying 65 euro for the plan and the handy.