Hi,
Yes indeed you can read about the rate limiting that we use in our systems here. Reading the details of your requests, it’s very likely that you are hitting the limits.
With your use case, it makes much more sense to request multiple dates in each request as you are only requesting a small area of interest. I suggest reading through this example in our Sentinel Hub Python documentation, and also have a read through this recent thread on the forum. Both these examples should help you out I think 