There are some odd "6050" boards out there. You may find that the ones which do not calibrate have a chip marked 6050A and/or they give a 0x98 response to the "Who_on_1" request rather then the expected 0x68. See a previous post of mine at MPU 6050(A) module problems - WHO_AM_I reports 0x98, not 0x68 as it should. Fake MPU 6050. The odd thing is that these chips will run code for the accelerometers if you tweak the sketch so that 0x98 is an acceptable answer to the "who_am-I" request and use the default calibration data. This is odd because if the chip is really a ICM-20689 (as suggested in my earlier post), the data registers for the accelerometer data should be in a different place - but it appears they aren't. They appear to be in the right place for a 6050.
The GY-25 board has a 6050 on it (not a 6050A), so I have no idea what's going on. The boards from China are cheap enough to just throw away if they don't work. I think the trick may be to do that rather then try to figure out why they don't work! I've given up on the GY-25 I think. Not worth wasting my time on it.