Unable to pair my Garmin Venue Sq with my iPhone

Are you pairing it through the Garmin Connect app as the instructions specify?

Pairing Your Smartphone

To set up the Venu® Sq device, it must be paired directly through the Garmin Connect™ app, instead of from the Bluetooth® settings on your smartphone. 

1. From the app store on your smartphone, install and open the Garmin Connect app. 
2. Select an option to enable pairing mode on your device: 

• • If this is the first time you are setting up your device, press  to turn on the device. 
  • If you previously skipped the pairing process or paired your device with a different smartphone, hold , and select  > Phone > Pair Phone to manually enter pairing mode. 
• 3. Select an option to add your device to your Garmin Connect account: 
  • If this is the first device you have paired with the Garmin Connect app, follow the on-screen instructions. 
  • If you have already paired another device with the Garmin Connect app, from the  or  menu, select Garmin Devices > Add Device, and follow the on-screen instructions.

https://www8.garmin.com/manuals/webhelp/GUID-1C3C7630-B695-44C3-AF56-949C1D4889FB/EN-US/GUID-412BCE52-57D8-4660-B7C4-306F9091426F.html

It might help if you explain what a "Venu sq" is.

I'm just guessing that it's some sort of Bluetooth accessory. If so, start here:

Pair a third-party Bluetooth accessory with your iPhone or iPad - Apple Support

When we looked it up in the search...

“To set up the Venu® Sq device, it must be paired directly through the Garmin Connect™ app, instead of from the Bluetooth® settings on your smartphone. “

It was written, but... (… don't know...)

Please check it, just in case,

Thank you very much, too.

We are looking forward to working with you in the future.