I would like to share with you a problem that I have in my work and I would be grateful if you could share your opinion on it.

It is about a truck detained by the Bulgarian customs at the border between Greece and Bulgaria (internal EU border), transporting non-excise goods from Greece to the Czech Republic. These goods arrived from China in a container and were placed under customs procedure 42 in Greece. The Greek customs office has carried out the actions provided for in the legislation (documentary and physical checks) and as a result has decided to allow the procedure, as a result of which, at least in my opinion, the goods become of Union status. The Bulgarian customs has claims for complete unloading of the goods in order to check whether the goods correspond in type and quantity according to the submitted documents.

In view of the above, I have put the following questions to the Bulgarian customs and I am still waiting for an answer. I would be very grateful if you could share your opinion on them:
1. Are applicable art. 188 – 190 of the UCC and Art. 238-239 of Commission Implementing Regulation (EU) 2015/2447 regarding Union goods, which goods are not under customs supervision?
2. Do customs authorities have powers to carry out any checks on Union non-excise goods, and if so, with what scope and purpose?