Web request crashes on devices with Android 8

Hello. Lately we are getting a lot of crashes exclusively on Android 8 devices. Our app crashes because of OutOfMemeryError exception. The exception is thrown in a thread that is used by UnityAds. Check out stack trace of the crash:

The above screenshot is not that representative, it looks like device is OOM already. But we get a lot of weird crashes when unity tries to allocate big chunks of memory (200mb - 2Gb). Also crashes are not that exclusive anymore.
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