The interview is very sudden, not sure whether it is because of the covid, it was done through phone call. I only talk to the direct manager and he asked me about my expected salary, which I thought should be HR's job

The company is all about automation. You need to be well verse in technical background. Ypu really need to think out of the box if u really want to stay in the company for long. You can expect a lot of technical questions to be asked.