I have a RECIPIENT_LIMIT_EXCEEDED error but only passing one recipient

Hello everyone, I hope you are all well. I am integrating with Docusign using the PHP SDK in Laravel. Everything was working perfectly until a request came up that I should have 2-factor authentication. I did it via SMS. I was able to send 1 envelope successfully. After that, I am only receiving this error:

"error_code" => "RECIPIENT_LIMIT_EXCEEDED"
"message" => "The recipient limit on the envelope has been exceeded. The cumulative recipient limit has been exceeded."

I am only sending 1 recipient.

A part of my code:

Note: I changed the phone number to an example one but I am passing on the real one.

        $signers = [new Signer([
            'email' => $client->email,
            'name' => $client->full_name,
            'recipient_id' => '1',
            'client_user_id' => $client->user_id,
            'tabs' => new Tabs(['sign_here_tabs' => $signHereTabs]),
            'email_notification' => new SignerEmailNotifications([
                'send_email' => false,
                'supported_language' => 'pt-BR',
                'suppress_emails' => true
            ]),
            'identity_verification' => new RecipientIdentityVerification([
                'workflow_id' => $this->workflowId,
                'input_options' => [
                    [
                        'name' => 'phone_number_list',
                        'valueType' => 'PhoneNumberList',
                        'phoneNumberList' => [
                            [
                                'countryCode' => '55',
                                'number' => '44999999999',
                            ]
                        ]
                    ]
                ]
            ]),
        ])];

        $envelopeDefinition = new EnvelopeDefinition([
            'email_subject' => 'Documentação versa',
            'documents' => $documents,
            'recipients' => new Recipients(['signers' => $signers]),
            'status' => 'sent',
        ]);

        $envelopeApi = new EnvelopesApi($this->apiClient);
        $envelopeSummary = $envelopeApi->createEnvelope($this->accountId, $envelopeDefinition);
        $envelopeId = $envelopeSummary->getEnvelopeId();

One of my questions is, can I authenticate via SMS in a sandbox account?
Thank you.