As joebloggs rightly says, TOIEC is significantly easier than IELTS.
TOIEC is at level A1 of the CEFR (Common European Framework of Reference) This is the needed level for Visa Application
Next level UP is A2 of the CEFR
Next level UP again is B1 of the CEFR (The IELTS is tested at minimum B1)
By the way, it doesn't matter that you failed at Reading Test as UKBA requires you to demonstrate a basic A1 level command of English for speaking and listening ONLY
You do
not need to demonstrate reading or writing skills at all.
Anyway, very best of luck for your test. You'll be fine.