unwilling to replace device, even with clear explanation of why we cannot remove the device

we purchased a gcom520 gate controller from them, but since the start, the device did not work as it was supposed to. every 3 days it does not work, then we have to reset the device, which is not how it is supposed to work. we had another unit before this one, which unfortunately broke, but the previous one worked ALL the time, with no need for any reset. I have contacted the company several times, but they refuse to replace the unit, as they want us to bring the unit in, so they can test it on-site, and only there-after are they willing to replace it should they not find a fix.

we are not able to have the device removed, as we require access control to this building. the reason why we installed the unit in the 1st place was due to vandalism, and to fix up the damages, cost us almost R100 000, and we are not prepared to go this route again.

we have explained this to them, but they are unwilling to come up with an alternative solution from their standard warranty policies. we just want a replacement unit, to make sure the building is not accessible by unwanted parties, who might vandalize the premises again.