Hi ,
Please confirm that there are no "limits" set on the VM in question by right-clicking the VM > Edit Settings > Resources Tab > Memory. Ensure that the "unlimited" is checked (it should be checked... best practice). If there was a limit set on your VM, you may need to perform a full powercycle of the VM to get the benefits after making the change.
Also keep in mind that the ESXi host itself needs 4GB RAM (minimum is 2GB to powerup the host, but it really wants 4GB for production workloads). Since your 2 VMs (10GB and 4GB) add up to 14GB RAM, you are currently only leaving 2GB (bare minimum and not recommended) for your host. You should be fine, but if you plan to remain memory constrained (i.e. only 16GB) and continue to push the limits like this you might consider adding a local SSD to handle the swap spillover (see Swapping to Host Cache) .