Cell reception can vary with humidity and indoors. I am not aware of Kmart stores blocking cell reception. My phone works wonderfully at our local Kmart. I hope this helps.
If you allow me to be your Free Personal Shopper. I can help you find coupons, lowest prices, great deals! I can also create custom catalogs to make your shopping experience more enjoyable. I do the work for you! New clients receive a welcome email with points to purchase at Sears or Kmart. Simply click this link: syw.co/MomssearchToSavings
then click on "Become a Client" orange button and you are good! Looking forward to having you on my team and saving even more!