Hello @tanja.baccega,
Please see this document on the Eikon Data API Limits. You will have to ensure that your application does not breach these limits, or else it might get throttled.
If the requirement is to analyze thousands of instruments, then a bulk feed product like DataScope Select might be more suited. It allows downloading a bulk file, either on demand or on schedule and then your application can piecemeal its way through it. Please contact your Refinitiv account manager, if you are interested in DSS.