IOSS number for EU countries

Hi!

For importing goods to EU in the IOSS mode, the local authorities of Czech Republic require end customers to pair packages Tracking number with IOSS number of the company who collected the VAT. Without the IOSS number, the VAT will be collected again and customer is charged a customs processing fee ~$10.

Where do I get JLCPCB's own IOSS number? It should look something like IM2760000742

Thanks!