Variations keep resetting/changing

When I have 35+ variations (never over 40) on a single product I am receiving a reoccurring issue where I enter in the variation details, click ‘Update’ and a couple of the variations will automatically untick ‘enable’ and the price will erase.

It seems to be different every time. Sometimes the variation weight and dimensions will erase, sometimes the variation will be deleted all togehter. If I then go in and update the corrupt variation it will change another and un-enable it.

I figure this is a memory issue in the db but the Memory limit was set at 64mb. I then changed it to 512mb but still having this issue.

Has anybody else experienced this and found a fix?

https://www.ads-software.com/plugins/woocommerce/