Check and resolve errors on wordpress contact form

I've been getting orange spam warnings on all my contact form completions, I changed host late 2021 but my emails are hosted in a different ISP.

Both providers have ran tests and the problem cannot be diagnosed, I'd appreciate it if I can pay someone a fixed fee to investigate and quote for resolution.

I will provide backend credentials and cPanel login to both hosts, together with previous exploration information that's been carried out.

At this point just quote me for the initial poke around. Not an urgent job, this does not have to be done today for example as it's been a problem for around 6 months.

I'm wondering whether my domain is the issue (14 years aged), the contact form 7 in Wordpress, or an ISP problem. This is a placeholder budget at £20, feel free to bid the rate you require.

** I'm not able to share the domain here due to previous issues with cold emails from overseas accounts following previous job posts for other requirements. I'm inundated with Skype calls, texts, emails etc so apologies for my concerns.

** Please begin your bid with 'Crazy Cat Lady' thank you.