DSMR smart meter change: one incorrect reading. How to remove?

Hi,

Last week I received a new smart meter (P1 DSMR) since we switch from 1 to 3 phase.
Now my wife noticed there is an error in the gas consumption noted. As you can see there is an abnormal usage of almost 5000 m3 july 14th, instead of the regular summer usage of around 1 m3 per day. This reading seems to be the old smart meters final reading. The new one starts with 0.
The meter is connected to home assistant by means of the DSMR smart reader “Smartgateway” https://smartgateways.nl/product/slimme-meter-wifi-gateway/

Is there a way I can remove this reading and replace it with something making more sense? Any help appreciated!
(yes, the wife finally starts to use it :partying_face: )

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