VODACOM AIRTIME MISSING

Good day, 2 Numbers that are for samsung smart watches have not been used in the last 2 months, should have accumulated the airtime on both numbers. These sim cards do not stay in a mobile device only get inserted when needed. Yet the airtime which should have accumulated on the 1 sim was only at R35.00. The other 1 had accumulated the airtime but finished within a few hours, which only a few short calls were made. If this is not sorted out i will be deducted the money from next months payment for the last 2 months until the problem is resolved. I do not want to be told that the sims were in use, when they were not, also i would like to see where and how the sims were in use. Unless there are duplicate numbers and someone else has usage to the airtime. 14.07.2020 was the first time sim cards were inserted into tablet. Airtime could not have even been used for data as there is wifi available. Please resolve this matter urgently.