@nitzdut82 if after following suggestions of the other two members and your My Account is still showing the previous plan, is the plan still showing as an option in your My Account to change to?
If so, go ahead and schedule a plan change to it changes on next renewal. If you change now you will lose out on funds already paid on the existing plan (no prorating).
If this was a plan change for an offer you do not see in your plan offerings you may need to inquire about this to a CSA. If so, submit a ticket to them though SIMon Chatbot found at the bottom of this community page or in the Get Help section at the top of the page.