ESA stopped; reinstated at lower level.

First post on this invaluable site - thanks for all your hard work.
Last year I was transferred from IB to ESA(Support Group) after submission of ESA50 (using the vital information here) without a medical. I was sent another ESA50 6 months later. My ESA was stopped completely (in a letter dated 2 days after the form was due) because the DWP said it had not been recieved. I asked for a reconsideration and sent a copy of the Certificate of Posting which I believed showed it had been returned on time. After hearing nothing for 10 weeks I rang, was told there was no record of my letter and somone would call within 4 hours. No one did but I received a letter with the same date as I called telling me they are 'pleased' to pay me ESA and it is from the date it had been stopped. However it is at the basic rate; there is no explanation as to why and it looks to me like a standard letter. I am reluctant to ring as on the last 2 occasions I was given wrong information. I am confused (and very stressed) and am intending to write and ask precisely what my position is and why I wasn't reinstated into the Support Group until my new form had been considered. I suppose I will also need to ask for a reconsideration or appeal. I thought it might just be a mistake but have also just received a letter calling me to an interview with a Personal Adviser - really worried about this and another issue to be tackled.
I was wondering if anyone is aware of the DWP adopting this approach or has any thoughts before I write again. Thanks

Hello and welcome to the site. As yopu are new, you might find this helpful

Welcome to Benefits and Work

The procedure should be that you remain in the support group until a decision is made otherwise. You should not have to go to then assessment phase as you are not a new claimant.

You might want to complain to DWP about your treatment

Complaining to DWP

or you might want to get your MP involved

Contacting your MP

Thank you both for the replies. You may be right Gordon as this is in line with what the DWP seem to be doing. However I may have been unclear. When I first found out that my ESA had been stopped by way of a P45 I phoned the DWP and was told the claim had been 'shut down', the ESA50 had been received that day (and that it can take up to a week because of it being sent to a PO Box), was now with the Decison Maker to consider and I should hear something the following week. He then said the claim had been 'suspended'. When I asked if there was anything I could do I was told no. The next day I received the standard letter saying my ESA had been stopped because I had failed to return the ESA - this had the same date as the P45 letter. I then wrote asking for a reconsideration and included the certificate of posting and the letter was signed for by the DWP. Nothing was heard until the most recent letter possibly prompted by my call. It is unfortunate the DWP do not seem to have to reply specifically to my reconsideration letter. I have not yet submitted a formal appeal using GL24.
As you say I will just have to write now for clarification but if I do not hear soon I suppose I will have to formally appeal against the decision in the last letter - I have only under 2 weeks because of Easter and illness.
Also have I any option other that to attend the interview with the Personal Adviser in 3 weeks? Thanks

Thank you Gordon.
I'm assuming the recent letter reinstating ESA at the lower rate is the result of my reconsideration letter concerning the original decision to stop payment and it is this last decision I am going to query: the apparent illogicality of it baffles me. And it will be this last decision I think I will have to appeal against and I have 12 days left.
I should have followed the advice on here and appealed at the outset - I had stupidly thought a reconsideration might be quicker!
I will keep you informed.