I spent years bending over backwards to accommodate the XH to have the kids in the holidays during his numerous times of unemployment.
It was unsettling for the children & I as we never knew what was happening despite my efforts to try to make plans with him.
My XH had written into the parenting agreement we had he share half the holidays yet when it came time to he never did.
After years of this & lots of text bullying/abuse from him I applied to the court for counselling to sort out our issues.
Now I'm in a completely different country to you but I was able to go through counselling which he had to take part in but chose to have separate sessions & this was a free service. Then the parenting agreement was altered at no cost to either of us.
Unfortunately he would not agree to anything regarding any of the holidays so it was taken out & noted it wasn't agreed upon.
Some countries have free court services in way of counselling or mediation.
Could you contact the court to find out?
Now I am battling custody issues 7 years later after court proceedings were started against me & it is my belief that once the court have set down an "order" the only way to change it is to go through a lawyer.
Alternatively though maybe you could apply to the court to have changes made & represent yourself?
I must tell you that after all this & my XH trying to get shared custody after returning from living abroad for 21/2 years that we had him agree to half the holidays then when he got a job he wouldn't sign & won't commit. Says it all really.
I sympathize with the disruption particularly when you're a working Mum like I am who has to plan just to operate on a daily basis.
Hang in there.