RangeException error during payload encryption with PHP JWT Framework

I’m trying to encrypt the payload using JWT Framework v2.2 as follow

$jws_payload = "sdvsd.....";
$kid = "AH1111";

$keyEncryptionAlgorithmManager = new AlgorithmManager([
    new RSAOAEP256(),
]);
$keyEncryptionAlgorithmManager = new AlgorithmManager([
    new RSAOAEP256(),
]);
$compressionMethodManager = new CompressionMethodManager([]);
$jweBuilder = new JWEBuilder(
    $keyEncryptionAlgorithmManager,
    $contentEncryptionAlgorithmManager,
    $compressionMethodManager
);

$jwk = new JWK([
    'kty' => 'RSA',
    'n' => $public_key_plain,
    "kid" => $this->kid
]);

$jwe = $jweBuilder
    ->create()              // We want to create a new JWE
    ->withPayload($jws_payload) // We set the payload
    ->withSharedProtectedHeader([
        'alg' => 'RSA-OAEP-256',        // Key Encryption Algorithm
        'enc' => 'A256GCM', // Content Encryption Algorithm
        'kid' => $kid            // We enable the compression (irrelevant as the payload is small, just for the example).
    ])
    ->addRecipient($jwk)    // We add a recipient (a shared key or public key).
    ->withAAD($aad)
    ->build(); 

but following fatal error thrown:

RangeException: Base64::decode() only expects characters in the correct base64 alphabet in ...jwt-framework-2.2.xvendorparagonieconstant_time_encodingsrcBase64.php on line 229

I found it thrown when trying to decode each 4-chars block of public key including slash character like fbf/