Neither is correct. You have a very long, very complex sentence. This has resulted in many errors and confusion. Try to split the sentence up into shorter, simpler segments.
"... of the calling reach ..." and "... of the calling reaches ..." are both wrong because you need a noun in each e.g. "... of the calling [noun] reaches ..." Insert the noun of your choice.
"... the call times ..." Is this supposed to be a number of times or a length of time? To put another way, is the limit 6 calls or 6 minutes.
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