wifi connection disconnected

[zophini]

I have noticed in the past several weeks that when I am in a building with wifi my wifi shows connected but I am not able to connect to any app. When I go to setting and wifi I have a message there is no wifi connection. I then have to tap on ?re-connect? and wifi calling will re-connect. But it will happen again sometimes within minutes sometimes after several hours. Any ideas???? Thanks in advance.