I am afraid that you cannot track a SIM card, I do know that iPhones have Find My iPhone and Android depending on Brand also have a similar tool if it has been setup, the only things that is require for these services to work is that the phone has power and the service is turned on. If the phone has a dead battery then using these services will only show the last position before the power went off, and with iPhone that is very limited on how long it will store the last position on your Apple account, iPhone can do found using https://www.icloud.com/find with android you can use https://www.google.com/android/find
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Thank you so much for your post and welcome to the community forum team! It's great to have you hear.
I am so sorry but just to confirm the advise given by @DJ_Shadow1966 we are unable to track a phone via the SIM. Can I ask if the above advise has helped at all and have you been able to locate the phone?