A mature plant just starting to flower split low at a Y

[JoseyWales]

4 weeks ago one of my plants split at a Y low on the plant, I taped it up with electrical tape and she did well with no problem. the last few days it's been hot and I noticed the the branches that where split are not taking up water and I think it's due to the split. I moved the tape and i think i seen the joint move not a good sign. Is there a fix I could try?