Major Speed Issues

I have a problem with my server possibly or maybe my wordpress version or maybe something else as i’m unsure to be honest.
I moved my server VPS, from Fasthosts to Webhostsuk about 22 months ago, and ever since then i have had huge problems and a massive decline in site traffic. I have been on to the support at WebhostUK almost daily since then with problem after problem, which they have sorted eventually but it has been a hard slog.
The reason i moved was because they were offering free SSL certs which i needed because i wanted to change my sites from old HTML4 type to wordpress ecommerce.
I have had many different problems since moving, with my site not being up, my provider saying that i was using to much memory and this was why it was freezing and shutting down and that i needed to upgrade and pay another ￡50 a month, when in reality my sites were less than 1 / 10th the size that they were when i was with fasthosts and i had no problems there, eventually after arguing with them over the issue and getting them to monitor the memory usage, they agreed that mine was using nothing at all (but it still crashing/kept shutting down every few days).
I had my concerns that it was wordpress which was causing this (i only have one site converted to wordpress which was bigmarquees.co.uk and one site which i had started to build and then subsiquently stopped because of the problems i was having, which at this time remains just a home page and a handful of products proforme.co.uk , and a page which i left in the old HTML format
Now to my latest problem which is what i need someone else’s views on please – If i did a google speed check on my site bigmarquees.co.uk it came back as 1/100 speed (Really Bad) if i did the same test on proforge.com it came back as 4/100 (really bad again) proforme.co.uk was 3/100
I complained about this to Webhostuk.co.uk and they said it was because my site needed optimising. I said that i understand this, but no amount of optimisation on images etc is going to make this site run at 90/100 which is considered a fast speed so something must be wrong! I had to get on and on at them for a long time, eventually they changed the server i was on again (this had been done before with the shutting down issue months ago and that issue was solved by a server change) and as soon as the server was changed my google speed check for proforge.com came out at 96/100 AMAZING!!! i was on cloud nine! but then when doing the speed test on the wordpress sites the increase was very minimal – on bigmarquees.co.uk the speed test was 4/100 and on proforme.co.uk it was better, but the site has very little to it 26/100.
Now i know i need to change the images to JPG200 and also other optimisations need doing to increase speed. but i feel like the company i am using is causing demise to my company by not being straight with me and im unsure if its worth spending time fixing these issues on this site to find out that they have little effect. Right now they are saying there is another problem (after me asking how come the proforge.com site went to 96/100 and is 10 years old with old HTML code, but the wordpress sites had little difference) and the other problem is down to the wordpress version needing updating and that they have done this now so everything should be good, but when i checked the speed had not increased, but then when i told them this they then said that it would take a few days to take effect? I just feel that they always have an excuse and always within a few days to a few weeks of constant complaining, they will change their minds and move to saying the problem is now something else… but nothing ever seems to get any better.
Can i ask, does the wordpress version cause the server to respond so slowly or is it as i expect the server and the company webhostuk? also, shouldn’t they be offering the most up to date version of wordpress on the control panel as the server and control panel i am using at the moment is brand new! also, i build my own websites and have not had much experience with wordpress and maybe its me thats doing something wrong?
Can someone please help me – As I’m at the end of my tether here, my sites have lost 95% of the traffic that they had two years ago and my income has dived to the point where im not making enough to live on anymore and i can’t seem to sort any of these problems out successfully, I wish i had paid someone to do this for me in the first place, but i have always built my own websites since 2002 and have always managed fine, but now im at a point where 2 years down the the line after changing host company to Webhostuk, i now don’t have the money to pay anyone and still can’t get a satisfactory answer from Webhostuk as to what is causing these issues. I am now trying everything and spending most of every day chasing this company trying to get answers as to what is going on and just being pushed from pillar to post, all the time loosing more customers and loosing googles respect as a website and a business.
Thanks in advance to anyone who can offer any advice.
Regards John

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