This is simply a myth, contacts can't be deleted automatically. Here is a Solution what you need to check when you are facing this kind of problem.
Solution :
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Solution :
- While saving contact check the location where you are saving the contacts. If you saving directly to google then you might be facing this kind of problem. To save contacts directly to Google you need Internet access all the time which is not possible for everyone. So need to change location of storage to Device or Sim. You wont face this problem after that.
Why?
The reason why your contacts are being deleted automatically is whenevet you are saving contacts to Google and your interney is not ON it will show the contact is saved but in actual its not. To access Google you need Internet so its not right to save contact directly to Google. When you save contact to google it needs to sync your gmail account so if internet is on and you save contact then you may see the saved contact afterwards but if internet is not on then you wont be able to see that contact again.
If you have any queries do comment below we will try to help you.