Set the global price strategy

Open Stores > Configuration > MageB2B > Pricesystem > Price select rule settings.

Choose the rule that should apply when no more specific Advanced Config rule is active:

• Lowest returns the lowest valid candidate.
• Highest returns the highest valid candidate.
• Sort order returns the first available price type in Price Priority Order.
• Individual price formula calculates a value from selected price types and appears with Advanced Config.

Save the configuration at the correct scope, clean the Price System cache and test one customer whose product has at least two competing prices.

Do not use Lowest merely because it sounds customer-friendly. Relative surcharges, minimum prices or a deliberately authoritative Customer Price can make Sort order the safer business rule.