diff --git a/src/covid.c b/src/covid.c
index 3a2cb67..b2b92e9 100644
--- a/src/covid.c
+++ b/src/covid.c
@@ -155,6 +155,9 @@ static void check_keys(struct k_work *work){
 
 		// we now generate the new interval identifier and re-encrypt the metadata
 		en_derive_interval_identifier(&intervalIdentifier, &periods[current_period_index].periodKey, currentInterval);
+
+   		en_derive_period_metadata_encryption_key(&periodMetadataEncryptionKey, &periods[current_period_index].periodKey);
+		   
 		en_encrypt_interval_metadata(&periodMetadataEncryptionKey, &intervalIdentifier, (unsigned char*)&bt_metadata, (unsigned char*)&encryptedMetadata, sizeof(associated_encrypted_metadata_t));
 
 		// broadcast intervalIdentifier plus encryptedMetada according to specs