A friend of mine got a Nitrado Minecraft (Vanilla) server. The server has a capacity of 4 players, has 2 GB of RAM and we play on the 1.16.5. If only three of us play everything runs smoothly, but as soon as there are four of us the server starts lagging hard (blocks are not broken down properly, you yourself are teleported back).
I wanted to ask if someone has the same problem and maybe knows a solution to the problem.
One solution would be to contact Nitrado Support to ask what's going on. That should be enough for 4 players. Otherwise, I recommend a server at MC-Host24, as they are cheap, high-performance and have no slot restrictions.