First of all, tell you that the wireless intercom must be reported to the local radio administration for the record, approved and issued with the corresponding frequency before it can be built. After the construction is completed, the Radio Administration will conduct on-site acceptance!

Whether you are in charge of the elevator or the basement. All need approval.

Note that the competent authority is the Radio Authority.

It is irresponsible to say that construction can be carried out without approval. They installed it for you. You paid for it. Then the radio authority found you. It's you who are unlucky. The country is now very strict with this piece of management!