Value added tax law (VAT)
An incorrectly prepared invoice can very quickly lead to additional claims for value added tax in a not insignificant amount (usually 19% of the invoice price), especially for deliveries across the border. In the "worst case", the customer (invoice recipient) can no longer demand the additional VAT to be paid. The company may experience liquidity difficulties or even the threat of insolvency.
I will be happy to advise you on these questions.