can anyone help me please. i have two newfys one male aged 15 months and a 11 month old female. Recently they refuse to come back when called and tend to run in the opposite direction. I have tried rewarding them when they come back but this no longer works.
If i walk the female separately the female will return. However when with the male he runs off she follows. This is all a great game to them but very exhausting for my husband who has to catch them.
They walk well on the lead, they sit when told(eventually) please can anyone help

When two of mine go through this stage (it recurs, sadly) I only let one off at a time.

Take them somewhere where they can't disappear and when they do this again just sit on the ground and wait, don't look at them directly or speak to them. They will come back when they realise that you wont chase or go after them and that something is more interesting where you are. When they come back get up without looking at them or speaking and turn around and walk the other way. When they come up beside you give them a treat, tell them they are good for walking with you and keep walking. If they run off again repeat the process sit on the ground etc. and eventually they will know that you wont play their game. After a few times ask them to sit and put the lead on and reward for sitting. Let them off again for a bit and repeat the process. They must not realise that eventually you will take them home. (if the ground is wet take a carrier bag with you to sit on) :-) You must try and make yourselves more exciting than what they think is exciting.:-)
Take your time over this and make sure that you have plenty of time and that you are not in a hurry to get back home for anything. This way you wont feel frustrated when it happens. Alternatively have them on a long line, not a flexi or halti/check chain and retrain the recall. Good Luck.

Being chased is a great game to a dog.  Have you watched dogs playing?  They just chase each other up and down.  Your husband, by chasing them, is playing with them and they think it's great fun, this 'come' game.  In fact, when they hear you call 'come' they probably think 'ah great, it's that running away game again' and sprint in the opposite direction. 

I'd go right back to basics - start calling them to you around the house for something VERY tasty.  Maybe some dried liver, some jerky, a whole sardine - that kind of level of tasty.  Do this many times until they instantly come to you for it.  Keep rewarding every time they come back immediately.  If they don't come back instantly, but muck around, don't reward even when they eventually come back.  They only get a reward for a fast, instant recall.  Then try it in the garden.  Then try it outside.  The first few times outside, don't let them get too far away from you before you call.  Call them back often and then let them go again - a recall should not always mean 'play time is over' or they won't want to come back!

If that doesn't work, I would go with the Lobster tail and Filet Mignon.

thank you for all your replies i will start trying to recall them in the house like suggested. i fully understand now that when my husband chases them they think it is a game, it does look funny though.
my main worry is that they may run up to someone and terrify them, by their size as they are not vicious.
I have enrolled them with a personal trainer and hope she can help me.
thank you to everyone who replied.