question regarding registration

Question

Hello,

I am planning a diary study over 5 days with 3 assessments per day. Additionally, there will be an entrance survey.

I expect around 130 participants.

I am now somewhat confused about which subscription is necessary for this. As I understand it, I collect personal data because I ask for email addresses (via opt-in, and then send all diary questionnaires as serial emails). Is that correct? And if so, which paid subscription do I need to choose? The one priced at 70€ states that "250 interviews" are possible. However, I would have 130 + 130x5 = 780 individual ones???

Thank you in advance for your advice!