It could be something as simple as not enough air in the beams or a twist in the tube, which could create a kink and make the beams susceptible to collapsing. 

Please deflate the beam and remove from the tent, re-inflate and pressure to 1 PSI above the recommended limit of your tent (remove the black pressure valve if required). When inflated out of the tent, check for twists in the inner tube, a bend in the beam indicates some kind of issue with the tube. 

If there is an issue with the tube then opening the sleeve and ensure the tube is flat inside the sleeve and is inserted all the way to the sleeve end and folded back if necessary.

Re- inflate the tube / beam, and make sure the end guylines are pulling the end beams apart. (i.e. away from the centre of the tent)

If this does not solve your issue, then please either submit a ticket or visit our spares website to purchase spare beams