When C1 took over the Walmart card I had, it was a disaster. When that card was Wally, I ONLY used it to purchase fuel as you used to get an automatic cents off. Which Wally did away with, they moved it to a discount on the bill. Then they sold it to C1. We got the new card and activated it and cut up the old Wally card. I set up an online C1 access and within a few days there was over $1000 charged! Not mine. No fuel. I then called them and they gave me the runaround. I cut up the card as they instructed and they sent a new one. I got the new one and used it once and there were new charges again. I called. I was THEN informed that the “Chip” was used on the first $1000 and since I ADMITTED I had the card, it was MY responsibility. It went on for months. Our USAA Bank told me that many companies don’t shut off the automatic “three failed chip reads and we enable the swipe to process”, which is how the cloned cards worked. I filed a police report in the small Texas town around 50 miles from here where all the charges were done. I called C1 to give them the PD report number and was told “We don’t do that”.  WHAT!?!?! I told them I was retired and they could just come after me. I also told them they are a CREDIT card company and charge that 4 percent for INSURANCE against fraud. The police contacted me a few months later and had arrested the long term criminal that was doing it. They had video of the person using the SWIPE and not the chip, they had video of attemps at the chip.
I still have the REI C1 card but have thought to never “have one in your wallet”. And I have a long-time friend who works for them!
I held my breath when REI became C1. So far it’s been OK. I didn’t know about losing rewards but I do remember that I was told that when I informed C1 they could stick their card, the Wally replacement, and cancel the account.