Business ProfileforCostco

Costco.com canceled my orders after confirmation, and I did NOT receive the full RETURNED MONEY yet. The customer service is very poor. Each agent's knowledge and skills are at different levels. Costco should make sure the return back. My order #********* was canceled after Costco confirmation email. I told the online agent I have thrown part of my used shop cards with 0 balance at the first time. She said it is an address problem and I could receive new shop cards and she has added a note. Several days passed, I received nothing. The second online agent said it is on the way. then 10days, the third agent said I should go Costco store to get my cards. then, at the Costco store, they confirmed 4 cards said they need online support. Then I come online and get shop cards numbers. In November, I go to the store on weekdays, a kind agent helped us and gave us the service number #******-****** and said we would receive new cards in 14days. We did receive half cards but the rest??? then, I talked with an agent, a new service number and the supervisor said she will help us to get it ASAP, a new Service Request # *************. But after several emails, she does not reply to any new emails. We thought it was solved as she said. but today, when I ask, the agent said FULLCARDNUMBER again??? We question them why they cannot reply to me with a new email? Why every time guarantee us what they cannot do? Why some agents can find numbers but next cannot? All " we apologize....." The shop cards I used are 5 cards, 1 still kept, 4 thrown out(0 balance at that time). Now receive 2 of them ($50 and $25) waiting for 2 cards ($50 and $15) PS: $15 is an apology card. That spend 4 months and no fault on me. And still waiting for $65. It looks like they want me to forget that money so that they choose to do nothing after the gaurantee. My family shops more than 20,000 dollars per year at Costco since 2017, but this time I was so disappointed. I might cancel my membership after this year.