iPhone not showing Wi-Fi icon but is connected to wifi on settings

It's possible your wifi connection is dropping even though your wifi setting is turned on. When this happens, your phone reverts to a cell connection & no longer shows the wifi icon. Turn your wifi setting off, then on & after you connect to your network, if your wifi icon is displayed. If you find that your wifi connection keeps dropping, contact your provider to troubleshoot.

My iPhone doesn't show the Wi-Fi icon in the top right corner, my husband's shows his on his iPhone. It has the blue check and the blue Wi-Fi symbol.