'All elements are outside the containers after migrating TYPO3 version and gridelements

I am in the process of migrating our website from TYPO3 version 8 LTS to 9.5 LTS.

I have problems with gridelements (old version 8.7, new version 9.81).

Everything is correct in FE but when I add content in BE the tx_gridelements_container, tx_gridelements_columns, and colpos fields are at 0.

All elements are outside the containers (at the top of the page).

The drag and drop works very well.

Any suggestions or changes I haven't seen.

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