Integrity check - invalid_hash

Hi.

I upgraded (via webadmin) my NC from 11 to 12(latest)

After upgrade I get the message: “Some files have not passed the integrity check.”

  • notes
    • INVALID_HASH
      • README.md
      • appinfo/app.php
      • appinfo/info.xml
      • appinfo/routes.php
      • controller/errors.php
      • controller/notesapicontroller.php
      • controller/notescontroller.php
      • controller/pagecontroller.php
      • css/notes.css
      • db/note.php
      • img/favicon-mask.svg
      • img/favicon-touch.png
      • img/favicon-touch.svg
      • img/favicon.ico
      • img/favicon.png
      • img/favicon.svg
      • img/notes.svg
      • js/app/controllers/appcontroller.js
      • js/app/controllers/notescontroller.js
      • js/app/services/notesmodel.js
      • js/public/app.min.js
      • js/public/app.min.js.map
      • l10n/bg_BG.js
      • l10n/bg_BG.json
      • l10n/ca.js
      • l10n/ca.json
      • l10n/cs_CZ.js
      • l10n/cs_CZ.json
      • l10n/de.js
      • l10n/de.json
      • l10n/es.js
      • l10n/es.json
      • l10n/es_MX.js
      • l10n/es_MX.json
      • l10n/fr.js
      • l10n/fr.json
      • l10n/hu_HU.js
      • l10n/hu_HU.json
      • l10n/ia.js
      • l10n/ia.json
      • l10n/it.js
      • l10n/it.json
      • l10n/ja.js
      • l10n/ja.json
      • l10n/nb_NO.js
      • l10n/nb_NO.json
      • l10n/nl.js
      • l10n/nl.json
      • l10n/pl.js
      • l10n/pl.json
      • l10n/pt_BR.js
      • l10n/pt_BR.json
      • l10n/ru.js
      • l10n/ru.json
      • l10n/sk_SK.js
      • l10n/sk_SK.json
      • l10n/sq.js
      • l10n/sq.json
      • l10n/sv.js
      • l10n/sv.json
      • l10n/tr.js
      • l10n/tr.json
      • service/notedoesnotexistexception.php
      • service/notesservice.php
      • templates/main.php

and one of these pr file:

[notes] => Array
(
[INVALID_HASH] => Array
(
[README.md] => Array
(
[expected] => d9cd815c04763e2f695f976123d008f7e76a6b6026d473f726b30d073b4633586159a2ff4c925ab175dcf56d8b36c320732389408ec635355b93b654cd5ba880
[current] => 871e860262ce61dd8c791b5fd1f16891f4e2eae47ba280cd031f4f65eca85f3c0849847c9b61e8363fd6d76c7031955f2ab136103540f9d0e07d2ec3e1ab5a8c
)

Any idea on how to fix this?

What did you do so far? Did other posts handling a similar error not help?

I tried a couple of things I found in the searches. It seems like the trick often is to replace the file with the installation package. I downloaded the install pack and unzipped it, did a search for one of the files (notesapicontroller.php) but it did not exist in the install pack.
Wanted to check with the experts before I do anything drastic.