Hello Steve and thanks for choosing the JustAnswer.com Phone Systems subcategory of the Electronics category.

Reset the controllers as follows:

• Remove the rechargeable batteries from each of the cordless handset(s).
• Unplug the main base power cord from the wall outlet. (Not to be confused with the remote charging base)
• Unplug the other end of the power cord from the main base.
• (If the main base also has a main backup battery, remove the battery.)
• ----- Wait 20 minutes. -----
• (The timing is very important --- 15 minutes is too short and 30 minutes may be too long. If you miss the time window, plug the unit back in for 5 minutes and start over.
• Re-connect the power cord to the main base.
• Re-install the rechargeable battery in one of the cordless handsets.
• Place the cordless handset in the main base.
• Re-connect the main base power cord to the wall outlet.

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• Try a different telephone jack in a different room/wall.
• If no change try a new phone cord.

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• If no change, request a remote line test from the local phone company.
• If inconclusive, have them check their lightning arrestor at the side of your building.