Hello Mohsen_54_2005,
Welcome to the community!
Unfortunately, I don't think what you intend is possible. Each SIM is associated with a specific line. Each line is associated with a phone number and particular plan. Regrettably, the plans are not transferrable between lines. If you wished to use the plan with greater data, you would need to use that SIM and adopt the phone number associated with that line and plan. I understand that is not what you may have intended, however, it is not possible to switch plans between lines.
If your main line needs additional data, there may be alternative plans available for that line. You should be able to view its options via your My Account.
Hope this helps š
Cheers
