I understand the theory of covered calls and have been looking into implementing this strategy in the following way:

Buy FTSE 100 cash index

Selling (writing) An In The Money (ITM) FTSE weekly call option

I have been researching this on IG markets

*(spread betting) since this is my preferred platform.*

However I have looked at 10 different ITM options, and none of them are profitable to open the position (will give an example)

Through all my research I have not come across this or any mention of the below problem:

Real life current Example (live data)

The weekly 6200 call option is priced at. 398 : 402 since we are selling we get the lower price)

Current FTSE cash price: 6600

Therefore loss on opening is : (398+6200) -(6600) = -2??

This would give a total value of the option less than the intrinsic value of the option?! None of the theory I have looked at mentions that the option would ever have effectively negative extrinsic value??

All of the weekly calls (even ATM) have similar pricing issues!

What is the correct profit formula in the above example?

Thanks for your help traders! Any real life current examples you could give would be great!