Rob Kardashian has wiped his Instagram account once again in the lead up to the premiere of his TV show.

The 29-year-old reality star surprised fans when he deleted all his photos and unfollowed everyone on the picture-posting app back in July (16), triggering rumours of trouble with his fiancee Blac Chyna, 28. While he didn't confirm what happened, with reports it was over messages he found on Blac's phone, Rob's account was soon up and running again.

However, just ahead of the premiere of his and his future-wife's reality series Rob & Chyna on Sunday (11Sep16), Rob has again deleted every single snap on his Instagram and no longer follows anyone - despite still having 7.1 million followers himself.

In an even more confusing turn of events, he decided to follow rapper Tyga, Chyna's ex-fiance and the current boyfriend of Rob's half-sister Kylie Jenner, before clearing everything on Thursday evening (08Sep16). Chyna and Tyga have son King Cairo, three, together, and Chyna is currently expecting a baby with Rob. It's thought this move could have been an olive branch as the expectant father awaits the birth of his first child.

Blac doesn't seem to be fazed by her beau's actions though as she posed up a storm on Snapchat on Thursday, wearing tiny pink shorts and a crop top showing off her growing baby bump. On the same day, a new clip from their upcoming series dropped, showing Rob and Blac taking turns to weigh themselves on a set of scales. Blac has spoken of her desire to put on pounds during her pregnancy, but Rob on the other hand is trying his best to slim down after getting gaining weight over the last few years.

"No lie, that's 20 pounds I gained. Damn," Rob exclaims in the clip, with Blac doing her best to reassure him.

"I told you we got to start running more and getting it in. Don't get down," she says.