my 4 month old won’t sleep in cot! help

[ForOchreBird]

my 4 month old has just started sleeping in a cot - originally in moses. he slept great the first night, 2nd night was okay but now he just wakes up instantly crying and just wont sleep in there. its keeping me up all hours. any advice?

Is it definitely the cot and not the sleep regression mixed with the drop in temperature?

i was thinking about what it could be, he is warm enough but has struggled with sleep recently but always went into his moses with no problems. may potentially be a mix of all just worried as sometimes i cant get him in there till 4/5am, i keep trying its just tiring