Game crashes on IOS at FontAtlasCache::releaseFontAtlas

During testing on different devices, a crash got reported on iPhone 4s (IOS 9.3.5) with 100% frequency. It always crashes when game level is about to start.
This crash so far has occurred only on the above mentioned device.

Log

I am attaching screenshot of crash log. It seems that this is an old issue as I have found similar issues online but none of them had a solution mentioned in it.

links are as follows.

https://github.com/cocos2d/cocos2d-x/issues/13773

https://discuss.cocos2d-x.org/t/ios-release-font-atlas-cache-crash/21393/4

Please help.

Thanks.