Insert new File to an external storage (S3) fails

Hello, i’m using nextcloud to connect to an S3 bucket as an external storage. every think is ok, it’s been mounted, i can visualize the diffrents files in this folder, i can delete or download them.
But the probleme is when i try to create a file or insert a new File using the drag & drop from the web ui. In fact, nextcloud displays a progress bar that remains stagnant as in the image

fewSec

Important thing, i can insert files to the S3 bucket using other application or java code (with the same secrtkey and secretaccesskey of caurse)

do you have any idea about the source of the probleme ?

Thanks a lot.

details:
Nextcloud version 15.0.2
Operating system and version Red Hat 4.8.5-16
Docker version 1.13.1-cs9, build 1bc62a2
docker pull link : https://hub.docker.com/_/nextcloud/
PHP version 7.1
Is this the first time you’ve seen this error? (Y/N): Yes

Relevant logging:
{“reqId”:“33Xx7z5Zlb6ruDf1C1na”,“level”:3,“time”:“2019-03-18T10:48:53+00:00”,“remoteAddr”:“10.31.206.212”,“user”:“amine”,“app”:“files_external”,“method”:“PUT”,
“url”:"/remote.php/webdav/Bucket%20applicatif/Documentation.docx",“message”:{“Exception”:“Aws\S3\Exception\S3Exception”,
“Message”:“Error executing “PutObject” on “http://bkt-ge003-002/Documentation.docx”;
AWS HTTP error: Client error: PUT http:\/\/bkt-ge003-002\/Documentation.docx
resulted in a 403 Forbidden response:\n<?xml version=\"1.0\" encoding=\"UTF-8\"?>AccessDenied</Code>Access Denied</Message></Resour (truncated…)
\n AccessDenied (client): Access Denied - <?xml version=\"1.0\" encoding=\"UTF-8\"?>AccessDenied</Code>Access Denied</Message>
</Resource>11223cf0ed4b9df26488</RequestId></Error>”,“Code”:0,“Trace”:[{“file”:"/var/www/html/3rdparty/aws/aws-sdk-php/src/WrappedHttpHandler.php",“line”:100,
“function”:“parseError”,“class”:“Aws\WrappedHttpHandler”,“type”:"->",“args”:["*** sensitive parameter replaced ",{“class”:“GuzzleHttp\Psr7\Request”},{“class”:“Aws\Command”},[]]},
{“file”:"/var/www/html/3rdparty/guzzlehttp/promises/src/Promise.php",“line”:203,“function”:“Aws\{closure}”,“class”:“Aws\WrappedHttpHandler”,“type”:"->",
“args”:["
sensitive parameters replaced "]},{“file”:"/var/www/html/3rdparty/guzzlehttp/promises/src/Promise.php",“line”:174,“function”:
“callHandler”,“class”:“GuzzleHttp\Promise\Promise”,“type”:"::",“args”:[2,"
sensitive parameter replaced ",[{“class”:“GuzzleHttp\Promise\Promise”},
{“class”:“Closure”},{“class”:“Closure”}]]},{“file”:"/var/www/html/3rdparty/guzzlehttp/promises/src/RejectedPromise.php",“line”:40,“function”:“GuzzleHttp\Promise\{closure}”,
“class”:“GuzzleHttp\Promise\Promise”,“type”:"::",“args”:["
sensitive parameters replaced "]},{“file”:"/var/www/html/3rdparty/guzzlehttp/promises/src/TaskQueue.php",“line”:47,
“function”:“GuzzleHttp\Promise\{closure}”,“class”:“GuzzleHttp\Promise\RejectedPromise”,“type”:"::",“args”:["
sensitive parameters replaced "]},
{“file”:"/var/www/html/3rdparty/guzzlehttp/guzzle/src/Handler/CurlMultiHandler.php",“line”:98,“function”:“run”,“class”:“GuzzleHttp\Promise\TaskQueue”,“type”:"->",“args”:[]},
{“file”:"/var/www/html/3rdparty/guzzlehttp/guzzle/src/Handler/CurlMultiHandler.php",“line”:125,“function”:“tick”,“class”:“GuzzleHttp\Handler\CurlMultiHandler”,“type”:"->",“args”:[]},
{“file”:"/var/www/html/3rdparty/guzzlehttp/promises/src/Promise.php",“line”:246,“function”:“execute”,“class”:“GuzzleHttp\Handler\CurlMultiHandler”,“type”:"->",“args”:[true]},
{“file”:"/var/www/html/3rdparty/guzzlehttp/promises/src/Promise.php",“line”:223,“function”:“invokeWaitFn”,“class”:“GuzzleHttp\Promise\Promise”,“type”:"->",“args”:[]},
{“file”:"/var/www/html/3rdparty/guzzlehttp/promises/src/Promise.php",“line”:267,“function”:“waitIfPending”,“class”:“GuzzleHttp\Promise\Promise”,“type”:"->",“args”:[]},
{“file”:"/var/www/html/3rdparty/guzzlehttp/promises/src/Promise.php",“line”:225,“function”:“invokeWaitList”,“class”:“GuzzleHttp\Promise\Promise”,“type”:"->",“args”:[]},
{“file”:"/var/www/html/3rdparty/guzzlehttp/promises/src/Promise.php",“line”:267,“function”:“waitIfPending”,“class”:“GuzzleHttp\Promise\Promise”,“type”:"->",“args”:[]},
{“file”:"/var/www/html/3rdparty/guzzlehttp/promises/src/Promise.php",“line”:225,“function”:“invokeWaitList”,“class”:“GuzzleHttp\Promise\Promise”,“type”:"->",“args”:[]},
{“file”:"/var/www/html/3rdparty/guzzlehttp/promises/src/Promise.php",“line”:62,“function”:“waitIfPending”,“class”:“GuzzleHttp\Promise\Promise”,“type”:"->",“args”:[]},
{“file”:"/var/www/html/3rdparty/aws/aws-sdk-php/src/S3/S3ClientTrait.php",“line”:33,“function”:“wait”,“class”:“GuzzleHttp\Promise\Promise”,“type”:"->",“args”:[]},
{“file”:"/var/www/html/lib/private/Files/ObjectStore/S3ObjectTrait.php",“line”:77,“function”:“upload”,“class”:“Aws\S3\S3Client”,“type”:"->",
“args”:[“bkt-ge003002”,“Documentation.docx”,null,“private”,{“mup_threshold”:524288000,“part_size”:524288000}]},
{“file”:"/var/www/html/apps/files_external/lib/Lib/Storage/AmazonS3.php",“line”:639,“function”:“writeObject”,“class”:“OCA\Files_External\Lib\Storage\AmazonS3”,“type”:"->",“args”:
[“Documentation.docx”,null]},{“file”:"/var/www/html/apps/files_external/lib/Lib/Storage/AmazonS3.php",“line”:469,“function”:“writeBack”,
“class”:“OCA\Files_External\Lib\Storage\AmazonS3”,“type”:"->",“args”:["/tmp/oc_tmp_oIAmyu",“Documentation.docx”]},
{“function”:“OCA\Files_External\Lib\Storage\{closure}”,“class”:“OCA\Files_External\Lib\Storage\AmazonS3”,“type”:"->",“args”:["
sensitive parameters replaced ***"]},
{“file”:"/var/www/html/apps/files_external/3rdparty/icewind/streams/src/CallbackWrapper.php",“line”:109,“function”:“call_user_func”,“args”:[{“class”:“Closure”}]},
{“function”:“stream_close”,“class”:“Icewind\Streams\CallbackWrapper”,“type”:"->",“args”:[]},{“file”:"/var/www/html/lib/private/Files/Storage/Common.php",“line”:829,“function”:“fclose”,“args”:
[null]},{“file”:"/var/www/html/lib/private/Files/Storage/Wrapper/Wrapper.php",“line”:630,“function”:“writeStream”,“class”:“OC\Files\Storage\Common”,“type”:"->",“args”:
[“Documentation.docx”,null,null]},