Mango Concentrate Drum Bulging, how critical is this? what measures should we take?

Our Company get Organic Mango Concentrate with 28brix storage condition Ambient but from the stock we got 2 drum bulging so what shall we do it .How level of Critical is this.and can also other will be like this .what should measure we should have to take ?

If the storage condition is ambient then that implies that it is (theoretically) aseptically packed/filled. Bulging it most likely to be a result of failure of aseptic status - either due to problems with pasteurisation/filling, or more frequently due to a failure in the packaging. Occasionally you will find that aseptic bags develop small cracks/holes, often so small they're difficult to see, but sufficient to render the product non-aseptic and thus allow micro growth.
Bulging sounds very much like a yeast problem - if it gets in there then there are plenty of nutrients and nice warm environment so it will unfortunately grow rapidly. I'd therefore expect the drums to be useless.

You can open them to check this but be very careful when you remove the lids - the yeast will be producing CO2 and this is what is causing the drums to bulge. It can build up quite significant pressure and when you loosen the drum closure ring this pressure can fire the lid off with considerable force. If you can safely take the lid off then you may want to pierce the bag to reduce pressure build-up, as otherwise it will simply continue and eventually is likely to force the top off the drum and burst the bag.

Nonetheless before doing any of that I'd contact your supplier and get instruction from them, as the sensible course of action here is to reject the drums ;)