VPNs are usually the weak link here, especially for consistency.
If you want stable US targeting, switch to a US-based ISP proxy instead. They behave more like real residential users but with way better stability than mobile or VPN setups.
Pair that with a consistent setup
same IP for the account
same device
same session behavior
And keep the account tied to that environment long term.
VPN hopping or turning it on and off is exactly what breaks the “identity” and causes mixed geo signals like you’re seeing.