My iPhone 7 Plus is no longer connecting to my Wi-Fi connection

Try to reset your Network Settings:

Go to Settings > General > Transfer or Reset [Device] > Reset > Reset Network Settings. This also resets Wi-Fi

networks and passwords, cellular settings, and VPN and APN settings that you've used before, but no other data is affected. When done, restart your iPhone and test its wifi connection.

If the issue persists, contact Apple Support directly:--> Contact Apple for support and service or make an appointment (*) and have your device inspected at an Apple Store or AASP (Apple Authorized Service Provider) among this list:--> https://locate.apple.com/choose-country-region . After checking it out, they'll give you all the available options.

Regards

Giulio

(*) You can do it:

• Online:--> Genius Bar Reservation and Apple Support Options - Apple;
• Contacting a local Apple Store or AASP among the list provided above;
• Using the "Apple Store" app, available and downloadable from AppStore.

Does it only happens at home or with all different wifi networks?

You're most welcome