When using whisper-node, it blocks the rest of the requests in nest.js

Question

When using whisper-node, it blocks the rest of the requests in nest.js

async getTranscript(filePath: string): Promise<any> {
    const options = {
      modelName: 'base.en',
      whisperOptions: {
        language: 'auto',
        gen_file_txt: false,
        gen_file_subtitle: false,
        gen_file_vtt: false,
        word_timestamps: true,
      },
    };
    if (filePath) {
      return await whisper(filePath, options);
    }
    return null;
  }

If i remove this line return await whisper(filePath, options); then everything works fine, after putting it no request works in that project․

What is the problem? How to fix it?