Old Phone transfer difficulty
I gave my sister my old Phone (IPhone 5). I cleaned it and received unlock permission from ATT, my current carrier. My sister uses Consumer Cellular as her carrier. When she tried to get a SIM card for the phone from Consumer Cellular, they said that the phone is still associated with my account in iCloud. I checked and the phone is not listed. I had ATT check and they did not find the phone associated with my account. Is there a problem with Consumer Cellular? Is this an Apple problem? She lives a long distance from me, and it is difficult for me to try to figure out what is going on. Any suggestions or opinions? She could use a phone that actually works. Thanks for any information
iPhone 5