No need to worry about this mishap. The Schengen Borders Code provides a mechanism with how to deal with this and what is acceptable evidence of having exited:
The travel documents of non-EU nationals are systematically stamped upon entry and exit. If a travel document does not bear an entry stamp, it may be presumed that the holder does not fulfil, or no longer fulfils, the conditions of duration of a short stay. However, the non-EU-country national may provide any credible evidence of having respected the conditions relating to the duration of a short stay, such as transport tickets or proof of his/her presence outside the territory of the EU countries.
The only record they keep is the stamps in your passport. You can use the UK entry stamp to prove that you left. There’s nothing to worry about.
Currently, Schengen States do not have a central database in which entries/exits are recorded. The evaluation is soley done by physically checking the stamps in your passport.
Such a system is however in the process of being implementened: https://eur-lex.europa.eu/legal-content/EN/TXT/HTML/?uri=CELEX:32017R2226&from=DE
I would not worry too much about it. As long as you have other documents and UK stamps in our passport that clearly show you have not overstayed, you should be fine.
Credit:stackoverflow.com‘
5 Mar, 2024
4 Mar, 2024