transactions – Master Seed of Mycellium does not match the address of the Mycellium app produced for me

The MYCELLIUM wallet was created in 2017 – Master Seed was copied down, has been negotiating ever since.

Variable phones upgrade, always replacing the latest Mycellium and using master seed to recover, no problems.

Last week, the app was “acting up” – didn’t want to reconcile and seemed to be hanging up. I decided to remove it and replace / restore from main seeds. This time, an incorrect balance is shown, and does a transaction log as well as looking at a blockchain of a public key show more transactions after 2018 ?! (though been busy until last week!)

I used this site to generate the references derived from my main seed. It seems to be correct as the first 10 references are true to me and show me what MyCellium shows me. However, when I search (in the database of derived addresses) for a Mycellium-generated access address that I successfully used last week … that address is NOT found ?! I assume the addresses are used consecutively? I produced 5000 addresses and I still can’t find that address there!

Any insight / help / etc would be much appreciated! I have never imported other private keys into MyCellium, just used the addresses provided by the app, and created another HD wallet from inside the app.

Any chance to recover my lost coins?