@Mattheis, Dirk, Thanks for posting in Q&A. From the error message, I find the error is caused that the EncryptionKey you provided is not 32 bytes long. Based on my researching, one byte is the range 00000000 - 11111111 in binary, or 0x00 - 0xFF in hex. As you can see, one byte is represented in hex as a 2 characters string. Therefore, a 32-byte hex string is 64 characters long.
In the json, I notice the "encryptionKey" is only 32 characters. Please increase it to 64 characters to see if it works.
Hope the above information can help.
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