How to fix the error "You are making too many requests to Yandex Maps API Service"?

Question

Yandex maps

Recently, an error has appeared when using Yandex Maps:
{"statusCode":429,"error":"Too Many Requests","message":"You are making too many requests to Yandex Maps API Service. Check Terms of Service ( see https://yandex.com/legal/maps_api) "}
Free API is connected:

<script src="https://api-maps.yandex.ru/2.1/?lang=ru_RU&amp;apikey=ACVJ7VsBAAAAfSS6cgIAVLnRi1q0iH043DIGgZ25iZHlDRIAAAAAAAAAAAAPNPh4wuod8SF2ylX9eUu1ZgNmVg==" type="text/javascript"></script>

Before that, it worked fine for six months.
The limit of 25,000 per day could not be exceeded in any way. We do a maximum of 50-100 per day. What could be the problem?