Hi,i want to update to flarum version 16 but after installation error "HTTP ERROR 500".
Flarum is located in a domain name: mysite.fr/forum
My website problem :

My composer.json :
{
"name": "flarum/flarum",
"description": "Delightfully simple forum software.",
"type": "project",
"keywords": [
"forum",
"discussion"
],
"homepage": "https://flarum.org/",
"license": "MIT",
"authors": [
{
"name": "Franz Liedke",
"email": "franz@develophp.org"
},
{
"name": "Daniel Klabbers",
"email": "daniel@klabbers.email",
"homepage": "https://luceos.com"
},
{
"name": "David Sevilla Martin",
"email": "me+flarum@datitisev.me",
"homepage": "https://datitisev.me"
},
{
"name": "Clark Winkelmann",
"email": "clark.winkelmann@gmail.com",
"homepage": "https://clarkwinkelmann.com"
},
{
"name": "Matthew Kilgore",
"email": "matthew@kilgore.dev"
},
{
"name": "Alexander (Sasha) Skvortsov",
"email": "askvortsov@flarum.org"
}
],
"support": {
"issues": "https://github.com/flarum/core/issues",
"source": "https://github.com/flarum/flarum",
"docs": "https://flarum.org/docs/"
},
"require": {
"andre-pullinen/ads": "^0.2.8",
"askvortsov/flarum-categories": "^2.0",
"askvortsov/flarum-moderator-warnings": "^0.4.0",
"clarkwinkelmann/flarum-ext-circle-groups": "^0.2.3",
"clarkwinkelmann/flarum-ext-who-read": "^1.2",
"flarum/approval": "^0.1.0",
"flarum/bbcode": "^0.1.0",
"flarum/core": "^0.1.0",
"flarum/emoji": "^0.1.0",
"flarum/flags": "^0.1.0",
"flarum/lang-english": "^0.1.0",
"flarum/likes": "^0.1.0",
"flarum/lock": "^0.1.0",
"flarum/markdown": "^0.1.0",
"flarum/mentions": "^0.1.0",
"flarum/nicknames": "^0.1.0",
"flarum/pusher": "^0.1.0",
"flarum/statistics": "^0.1.0",
"flarum/sticky": "^0.1.0",
"flarum/subscriptions": "^0.1.0",
"flarum/suspend": "^0.1.0",
"flarum/tags": "^0.1.0",
"fof/analytics": "^0.11.0",
"fof/best-answer": "^0.3.2",
"fof/gamification": "^0.4.2",
"fof/links": "^0.5.3",
"fof/nightmode": "^0.7.1",
"fof/oauth": "^0.2.0",
"fof/webhooks": "^0.5.1",
"ianm/follow-users": "^0.1.2",
"qiaeru/lang-french": "^1.9"
},
"config": {
"preferred-install": "dist",
"sort-packages": true
},
"minimum-stability": "beta",
"prefer-stable": true
}