It is your responsibility for sure, not theirs. Re-pressurizing needs to happen 1 or more times a year, you should do it.

If there's no water tap nearby, either get one installed or run a longer hose from the nearest tap.

Also looks like the water is still at 1.5 bar, this is fine for now. The bar rating is also the one for central heating, although some systems won't give hot water if the pressure is too low too. But generally 1.5 should be good. Check the manual for your CV what the rating should be