Upgrades are ordered from within the service, not as a new order.
HOW
Services > My Services > click the service > Upgrade/Downgrade. Choose the new plan and review the prorated figure before confirming.
HOW PRORATION WORKS
You have already paid for the current period at the old rate. The system credits the unused portion and charges the new rate for the remaining days. The difference is payable now, and your renewal date does not change.
WHAT HAPPENS
Most upgrades apply to the same account on the same server immediately, with no downtime, no migration and no DNS change. Your new limits take effect at once.
Some upgrades, such as a move to a VPS, involve a migration. We will coordinate the timing with you.
WHAT NOT TO DO
Do not place a new order for the larger plan. That creates a second account, a second invoice and a migration you did not need. Use the upgrade path.
BEFORE UPGRADING
Check whether the problem is actually capacity. A slow site with no caching will be slow on a bigger plan too. Open a ticket and we will look at your usage first.