Hello Jessika
Thanks for posting in regards to your mobile phone bill and items contained, we appreciate the confusion caused and you taking the time to raise it via the forums. Welcome to the community.
Can you confirm if this is on previous bills? Do they show at the same time or different times or the same time each day? It could be the SIM registering on the network but this probably wouldn't show as a call. Voicemail has a different number also.
Rob