Entity Relationship Diagram - Did I design it the right way?

Question

I have to build an Entity Relationship Diagram and therefore wanted to ask you, if I did it the right way. Any help is highly appreciated!

Here is the assignment:

"Lisa is the owner of the cleaning company CleanAlp. Her company's primary customers are property management companies that manage residential complexes (properties). The customers book one or more services for every property. For this purpose, CleanAlp and the respective customer agree to a contract. There can also be more than one contract for one property (e.g. after termination and new assignment) or temporary additional cleaning services in exceptional cases. Every cleaning service has an interval (e.g. weekly, fortnightly, monthly), which has been agreed to in the contract. A cleaning service refers to a catalogue containing the cleaning services offered by Cleanalp (e.g. sweeping the stairwell, cleaning windows). Lisa employs several people. For each property, one employee is responsible for executing the cleaning services. The responsible person can change during the contract term, but it must be kept track of who and when was responsible. Invoices are sent to customers monthly—the amount to be paid as agreed upon in the contract."

My solution: Entity Relationship Diagram

Thank you very much!

Sincerely, Johann