General Settings will not save and says Support Contact must be 6–15 digits. What is wrong?

On Settings → Web Settings → General Settings, these must be filled before Submit works:

• Site Title
• Support Email, a valid email address
• Support Contact, 6 to 15 digits, numbers only

Pick your country code in the box to the left of the phone number, for example +91, and type the number without the country code, spaces or a leading +. If you fill the optional WhatsApp Contact, it follows the same rules and needs its own country code.

A warning message lists every problem, so fix each one and click Submit again.