Monster Scooter Parts 16x2.50 inner tube blew up putting air at 35 psi not putting enough information up on the website warning people. Colorado Springs Colorado

We are a repair shop out in Phoenix, Arizona. We sell electric bicycle, sell parts, and do repairs. A customer didn't have one of our bikes, but we fix any type of bikes.  We ordered the parts from Monster scooter parts.  I didn't think about searching the review on the internet about them.  The bike was a scooter. It needed a 16 x 2.50 bent valve. I ordered a tire from them too.  The ordering and shipment wasn't the problem.  The main problem was the tube. When you inflate the tube it exploded. So I called them.  They sent a replacement.  It exploded again.  They asked me how much air I put it in the tube?  I told them 35 psi.  He said, It takes 20 psi.  It doesn't make any sense to put little air in a tube.  If you put 20 psi in a tube that required 40 psi on the tire.  He said, You don't follow what the tire reads.  What is he talking about.  This company don't know much about putting air on the tube.  The scooter isn't a bike.  It's very heavy.  We normally do carry the 16 x 2.50, but we ran out of it.  We get it from China. If you put 20 psi on the tube it will go flat on a scooter that weighs over 200 pounds.  I asked to talk to a manager.  They don't have one.  I have two choices to get it replace for the third time which I need to put 20 psi or I can get a refund.  Get this they don't refund the shipping cost back to me.  So I get maybe $3.10 back.  Either way there is no win win situation.  They should have posted the psi on the website.  There is absolutely no way I want to get another tube.  The problem isn't fix. Of cause you need to read the tire psi.  You don't put air in the tire.  It's the tube that you need to put the psi. The tire has to put the air pressure reading for the tube.  I have no clue how these employees at Monster scooter parts think?  They said, This isn't the point.  What?  What point is what point? What are they saying.  Warning to all, don't buy their tubes!  It will explode try another company to buy parts.