Meta's engineering team investigated this issue and they indicate the problem is with companion devices specifically. They have identified the code causing a problem but a long term solution may take time.
In the meantime, Meta have provided a workaround (which is to clean the contacts database table, effectively performing a reset) that will remove the error and allow inbound messages to flow again. If you require this workaround, please contact our support team and we will initiate the reset on a number basis.
Note: Meta have removed this incident from their updated their status page.
