TAX ID not accepted on customer account creation
Summary
When you try to create a new customer account the TAX ID is a required field and must contain a valid value by default. You are however able to modify the field requirements to your taste.
Start
Go to 'Classic Panel'
Go to 'Billing'
Go to ‘Home’ > ‘System’ > ‘Settings’
Go to More Finance Settings > Country Specific Settings
Select the Country your customer is located in
Click Edit on the bottom of the page
To disable the field requirement set the option "If Tax Registration required for companies" to "Not required"
To modify the field requirement you can edit the field "Regular expression for company Tax ID" On this same page you can completly remove the field regular expression. You Tax ID will not be verified after this.
Default setting:
NL: ^(NL)? *\d{9}[Bb]{1}\d{2}$
BE: ^(BE)? *\d{10}$
Click Save to submit the new settings