Beats will not connect with iPhone 10
My beats 3 were connected by Bluetooth, but stopped working and then would not connect. I removed and now will not add.
What happens when you try? Have you done Beats reset and are they in pairing mode when you trying to connect them to your iPhone?
Reset your Beats on-ear or over-ear headphones
https://support.apple.com/en-us/HT201118
Reset your Beats earphones